LabVIEW 51 nodes, 5 structures, 10 diagrams

Teaching the elephant to tap-dance is never pretty. I'll, ah, skip the character count.

The program flows from left to right:

Ruby 1.9, 185 chars

(heavily based on the other Ruby solutions)

w=($<.read.downcase.scan(/[a-z]+/)-%w{the and of to a i it in or is}).group_by{|x|x}.map{|x,y|[-y.size,x]}.sort[0,22]
k,l=w[0]
puts [?\s+?_*m=76-l.size,w.map{|f,x|?|+?_*(f*m/k)+"| "+x}]

Instead of using any command line switches like the other solutions, you can simply pass the filename as argument. (i.e. ruby1.9 wordfrequency.rb Alice.txt)

Since I'm using character-literals here, this solution only works in Ruby 1.9.

Edit: Replaced semicolons by line breaks for "readability". :P

Edit 2: Shtééf pointed out I forgot the trailing space - fixed that.

Edit 3: Removed the trailing space again ;)

GolfScript, 177 175 173 167 164 163 144 131 130 chars

Slow - 3 minutes for the sample text (130)

{32|.123%97<n@if}%]''*n%"oftoitinorisa"2/-"theandi"3/-$(1@{.3$>1{;)}if}/]2/{~~\;}$22<.0=~:2;,76\-:1'_':0*' '\@{"
|"\~1*2/0*'| '@}/

Explanation:

{           #loop through all characters
 32|.       #convert to uppercase and duplicate
 123%97<    #determine if is a letter
 n@if       #return either the letter or a newline
}%          #return an array (of ints)
]''*        #convert array to a string with magic
n%          #split on newline, removing blanks (stack is an array of words now)
"oftoitinorisa"   #push this string
2/          #split into groups of two, i.e. ["of" "to" "it" "in" "or" "is" "a"]
-           #remove any occurrences from the text
"theandi"3/-#remove "the", "and", and "i"
$           #sort the array of words
(1@         #takes the first word in the array, pushes a 1, reorders stack
            #the 1 is the current number of occurrences of the first word
{           #loop through the array
 .3$>1{;)}if#increment the count or push the next word and a 1
}/
]2/         #gather stack into an array and split into groups of 2
{~~\;}$     #sort by the latter element - the count of occurrences of each word
22<         #take the first 22 elements
.0=~:2;     #store the highest count
,76\-:1     #store the length of the first line
'_':0*' '\@ #make the first line
{           #loop through each word
"
|"\~        #start drawing the bar
1*2/0       #divide by zero
*'| '@      #finish drawing the bar
}/

"Correct" (hopefully). (143)

{32|.123%97<n@if}%]''*n%"oftoitinorisa"2/-"theandi"3/-$(1@{.3$>1{;)}if}/]2/{~~\;}$22<..0=1=:^;{~76@,-^*\/}%$0=:1'_':0*' '\@{"
|"\~1*^/0*'| '@}/

Less slow - half a minute. (162)

'"'/' ':S*n/S*'"#{%q
'\+"
.downcase.tr('^a-z','
')}\""+~n%"oftoitinorisa"2/-"theandi"3/-$(1@{.3$>1{;)}if}/]2/{~~\;}$22<.0=~:2;,76\-:1'_':0*S\@{"
|"\~1*2/0*'| '@}/

Output visible in revision logs.

206

shell, grep, tr, grep, sort, uniq, sort, head, perl

~ % wc -c wfg
209 wfg
~ % cat wfg
egrep -oi \\b[a-z]+|tr A-Z a-z|egrep -wv 'the|and|of|to|a|i|it|in|or|is'|sort|uniq -c|sort -nr|head -22|perl -lape'($f,$w)=@F;$.>1or($q,$x)=($f,76-length$w);$b="_"x($f/$q*$x);$_="|$b| $w ";$.>1or$_=" $b\n$_"'
~ % # usage:
~ % sh wfg < 11.txt

hm, just seen above: sort -nr -> sort -n and then head -> tail => 208 :)
update2: erm, of course the above is silly, as it will be reversed then. So, 209.
update3: optimized the exclusion regexp -> 206

egrep -oi \\b[a-z]+|tr A-Z a-z|egrep -wv 'the|and|o[fr]|to|a|i[tns]?'|sort|uniq -c|sort -nr|head -22|perl -lape'($f,$w)=@F;$.>1or($q,$x)=($f,76-length$w);$b="_"x($f/$q*$x);$_="|$b| $w ";$.>1or$_=" $b\n$_"'

for fun, here's a perl-only version (much faster):

~ % wc -c pgolf
204 pgolf
~ % cat pgolf
perl -lne'$1=~/^(the|and|o[fr]|to|.|i[tns])$/i||$f{lc$1}++while/\b([a-z]+)/gi}{@w=(sort{$f{$b}<=>$f{$a}}keys%f)[0..21];$Q=$f{$_=$w[0]};$B=76-y///c;print" "."_"x$B;print"|"."_"x($B*$f{$_}/$Q)."| $_"for@w'
~ % # usage:
~ % sh pgolf < 11.txt

Transact SQL set based solution (SQL Server 2005) 1063 892 873 853 827 820 783 683 647 644 630 characters

Thanks to Gabe for some useful suggestions to reduce the character count.

NB: Line breaks added to avoid scrollbars only the last line break is required.

DECLARE @ VARCHAR(MAX),@F REAL SELECT @=BulkColumn FROM OPENROWSET(BULK'A',
SINGLE_BLOB)x;WITH N AS(SELECT 1 i,LEFT(@,1)L UNION ALL SELECT i+1,SUBSTRING
(@,i+1,1)FROM N WHERE i<LEN(@))SELECT i,L,i-RANK()OVER(ORDER BY i)R INTO #D
FROM N WHERE L LIKE'[A-Z]'OPTION(MAXRECURSION 0)SELECT TOP 22 W,-COUNT(*)C
INTO # FROM(SELECT DISTINCT R,(SELECT''+L FROM #D WHERE R=b.R FOR XML PATH
(''))W FROM #D b)t WHERE LEN(W)>1 AND W NOT IN('the','and','of','to','it',
'in','or','is')GROUP BY W ORDER BY C SELECT @F=MIN(($76-LEN(W))/-C),@=' '+
REPLICATE('_',-MIN(C)*@F)+' 'FROM # SELECT @=@+' 
|'+REPLICATE('_',-C*@F)+'| '+W FROM # ORDER BY C PRINT @

Readable Version

DECLARE @  VARCHAR(MAX),
        @F REAL
SELECT @=BulkColumn
FROM   OPENROWSET(BULK'A',SINGLE_BLOB)x; /*  Loads text file from path
                                             C:\WINDOWS\system32\A  */

/*Recursive common table expression to
generate a table of numbers from 1 to string length
(and associated characters)*/
WITH N AS
     (SELECT 1 i,
             LEFT(@,1)L

     UNION ALL

     SELECT i+1,
            SUBSTRING(@,i+1,1)
     FROM   N
     WHERE  i<LEN(@)
     )
  SELECT   i,
           L,
           i-RANK()OVER(ORDER BY i)R
           /*Will group characters
           from the same word together*/
  INTO     #D
  FROM     N
  WHERE    L LIKE'[A-Z]'OPTION(MAXRECURSION 0)
             /*Assuming case insensitive accent sensitive collation*/

SELECT   TOP 22 W,
         -COUNT(*)C
INTO     #
FROM     (SELECT DISTINCT R,
                          (SELECT ''+L
                          FROM    #D
                          WHERE   R=b.R FOR XML PATH('')
                          )W
                          /*Reconstitute the word from the characters*/
         FROM             #D b
         )
         T
WHERE    LEN(W)>1
AND      W NOT IN('the',
                  'and',
                  'of' ,
                  'to' ,
                  'it' ,
                  'in' ,
                  'or' ,
                  'is')
GROUP BY W
ORDER BY C

/*Just noticed this looks risky as it relies on the order of evaluation of the 
 variables. I'm not sure that's guaranteed but it works on my machine :-) */
SELECT @F=MIN(($76-LEN(W))/-C),
       @ =' '      +REPLICATE('_',-MIN(C)*@F)+' '
FROM   #

SELECT @=@+' 
|'+REPLICATE('_',-C*@F)+'| '+W
             FROM     #
             ORDER BY C

PRINT @

Output

 _________________________________________________________________________ 
|_________________________________________________________________________| she
|_______________________________________________________________| You
|____________________________________________________________| said
|_____________________________________________________| Alice
|_______________________________________________| was
|___________________________________________| that
|____________________________________| as
|________________________________| her
|_____________________________| at
|_____________________________| with
|__________________________| on
|__________________________| all
|_______________________| This
|_______________________| for
|_______________________| had
|_______________________| but
|______________________| be
|_____________________| not
|____________________| they
|____________________| So
|___________________| very
|__________________| what

And with the long string

 _______________________________________________________________ 
|_______________________________________________________________| she
|_______________________________________________________| superlongstringstring
|____________________________________________________| said
|______________________________________________| Alice
|________________________________________| was
|_____________________________________| that
|_______________________________| as
|____________________________| her
|_________________________| at
|_________________________| with
|_______________________| on
|______________________| all
|____________________| This
|____________________| for
|____________________| had
|____________________| but
|___________________| be
|__________________| not
|_________________| they
|_________________| So
|________________| very
|________________| what

Ruby 207 213 211 210 207 203 201 200 chars

An improvement on Anurag, incorporating suggestion from rfusca. Also removes argument to sort and a few other minor golfings.

w=(STDIN.read.downcase.scan(/[a-z]+/)-%w{the and of to a i it in or is}).group_by{|x|x}.map{|x,y|[-y.size,x]}.sort.take 22;k,l=w[0];m=76.0-l.size;puts' '+'_'*m;w.map{|f,x|puts"|#{'_'*(m*f/k)}| #{x} "}

Execute as:

ruby GolfedWordFrequencies.rb < Alice.txt

Edit: put 'puts' back in, needs to be there to avoid having quotes in output.
Edit2: Changed File->IO
Edit3: removed /i
Edit4: Removed parentheses around (f*1.0), recounted
Edit5: Use string addition for the first line; expand s in-place.
Edit6: Made m float, removed 1.0. EDIT: Doesn't work, changes lengths. EDIT: No worse than before
Edit7: Use STDIN.read.

Mathematica (297 284 248 244 242 199 chars) Pure Functional

and Zipf's Law Testing

Look Mamma ... no vars, no hands, .. no head

Edit 1> some shorthands defined (284 chars)

f[x_, y_] := Flatten[Take[x, All, y]]; 

BarChart[f[{##}, -1], 
         BarOrigin -> Left, 
         ChartLabels -> Placed[f[{##}, 1], After], 
         Axes -> None
] 
& @@
Take[
  SortBy[
     Tally[
       Select[
        StringSplit[ToLowerCase[Import[i]], RegularExpression["\\W+"]], 
       !MemberQ[{"the", "and", "of", "to", "a", "i", "it", "in", "or","is"}, #]&]
     ], 
  Last], 
-22]

Some explanations

Import[] 
   # Get The File

ToLowerCase []
   # To Lower Case :)

StringSplit[ STRING , RegularExpression["\\W+"]]
   # Split By Words, getting a LIST

Select[ LIST, !MemberQ[{LIST_TO_AVOID}, #]&]
   #  Select from LIST except those words in LIST_TO_AVOID
   #  Note that !MemberQ[{LIST_TO_AVOID}, #]& is a FUNCTION for the test

Tally[LIST]
   # Get the LIST {word,word,..} 
     and produce another  {{word,counter},{word,counter}...}

SortBy[ LIST ,Last]
   # Get the list produced bt tally and sort by counters
     Note that counters are the LAST element of {word,counter}

Take[ LIST ,-22]
   # Once sorted, get the biggest 22 counters

BarChart[f[{##}, -1], ChartLabels -> Placed[f[{##}, 1], After]] &@@ LIST
   # Get the list produced by Take as input and produce a bar chart

f[x_, y_] := Flatten[Take[x, All, y]]
   # Auxiliary to get the list of the first or second element of lists of lists x_
     dependending upon y
   # So f[{##}, -1] is the list of counters
   # and f[{##}, 1] is the list of words (labels for the chart)

Output

alt text http://i49.tinypic.com/2n8mrer.jpg ^[1]

Mathematica is not well suited for golfing, and that is just because of the long, descriptive function names. Functions like "RegularExpression[]" or "StringSplit[]" just make me sob :(.

Zipf's Law Testing

The Zipf's law ^[2] predicts that for a natural language text, the Log (Rank) vs Log (occurrences) Plot follows a linear relationship.

The law is used in developing algorithms for criptography and data compression. (But it's NOT the "Z" in the LZW algorithm).

In our text, we can test it with the following

 f[x_, y_] := Flatten[Take[x, All, y]]; 
 ListLogLogPlot[
     Reverse[f[{##}, -1]], 
     AxesLabel -> {"Log (Rank)", "Log Counter"}, 
     PlotLabel -> "Testing Zipf's Law"]
 & @@
 Take[
  SortBy[
    Tally[
       StringSplit[ToLowerCase[b], RegularExpression["\\W+"]]
    ], 
   Last],
 -1000]

The result is (pretty well linear)

alt text http://i46.tinypic.com/33fcmdk.jpg ^[3]

Edit 6 > (242 Chars)

Refactoring the Regex (no Select function anymore)
Dropping 1 char words
More efficient definition for function "f"

f = Flatten[Take[#1, All, #2]]&; 
BarChart[
     f[{##}, -1], 
     BarOrigin -> Left, 
     ChartLabels -> Placed[f[{##}, 1], After], 
     Axes -> None] 
& @@
  Take[
    SortBy[
       Tally[
         StringSplit[ToLowerCase[Import[i]], 
          RegularExpression["(\\W|\\b(.|the|and|of|to|i[tns]|or)\\b)+"]]
       ],
    Last],
  -22]

Edit 7 → 199 characters

BarChart[#2, BarOrigin->Left, ChartLabels->Placed[#1, After], Axes->None]&@@ 
  Transpose@Take[SortBy[Tally@StringSplit[ToLowerCase@Import@i, 
    RegularExpression@"(\\W|\\b(.|the|and|of|to|i[tns]|or)\\b)+"],Last], -22]

• Replaced f with Transpose and Slot (#1/#2) arguments.
• We don't need no stinkin' brackets (use f@x instead of f[x] where possible)

C# - 510 451 436 446 434 426 422 chars (minified)

Not that short, but now probably correct! Note, the previous version did not show the first line of the bars, did not scale the bars correctly, downloaded the file instead of getting it from stdin, and did not include all the required C# verbosity. You could easily shave many strokes if C# didn't need so much extra crap. Maybe Powershell could do better.

using C=System.Console;   // alias for Console
using System.Linq;  // for Split, GroupBy, Select, OrderBy, etc.

class Class // must define a class
{
    static void Main()  // must define a Main
    {
        // split into words
        var allwords = System.Text.RegularExpressions.Regex.Split(
                // convert stdin to lowercase
                C.In.ReadToEnd().ToLower(),
                // eliminate stopwords and non-letters
                @"(?:\b(?:the|and|of|to|a|i[tns]?|or)\b|\W)+")
            .GroupBy(x => x)    // group by words
            .OrderBy(x => -x.Count()) // sort descending by count
            .Take(22);   // take first 22 words

        // compute length of longest bar + word
        var lendivisor = allwords.Max(y => y.Count() / (76.0 - y.Key.Length));

        // prepare text to print
        var toPrint = allwords.Select(x=> 
            new { 
                // remember bar pseudographics (will be used in two places)
                Bar = new string('_',(int)(x.Count()/lendivisor)), 
                Word=x.Key 
            })
            .ToList();  // convert to list so we can index into it

        // print top of first bar
        C.WriteLine(" " + toPrint[0].Bar);
        toPrint.ForEach(x =>  // for each word, print its bar and the word
            C.WriteLine("|" + x.Bar + "| " + x.Word));
    }
}

422 chars with lendivisor inlined (which makes it 22 times slower) in the below form (newlines used for select spaces):

using System.Linq;using C=System.Console;class M{static void Main(){var
a=System.Text.RegularExpressions.Regex.Split(C.In.ReadToEnd().ToLower(),@"(?:\b(?:the|and|of|to|a|i[tns]?|or)\b|\W)+").GroupBy(x=>x).OrderBy(x=>-x.Count()).Take(22);var
b=a.Select(x=>new{p=new string('_',(int)(x.Count()/a.Max(y=>y.Count()/(76d-y.Key.Length)))),t=x.Key}).ToList();C.WriteLine(" "+b[0].p);b.ForEach(x=>C.WriteLine("|"+x.p+"| "+x.t));}}

Perl, 237 229 209 chars

(Updated again to beat the Ruby version with more dirty golf tricks, replacing split/[^a-z/,lc with lc=~/[a-z]+/g, and eliminating a check for empty string in another place. These were inspired by the Ruby version, so credit where credit is due.)

Update: now with Perl 5.10! Replace print with say, and use ~~ to avoid a map. This has to be invoked on the command line as perl -E '<one-liner>' alice.txt. Since the entire script is on one line, writing it as a one-liner shouldn't present any difficulty :).

 @s=qw/the and of to a i it in or is/;$c{$_}++foreach grep{!($_~~@s)}map{lc=~/[a-z]+/g}<>;@s=sort{$c{$b}<=>$c{$a}}keys%c;$f=76-length$s[0];say" "."_"x$f;say"|"."_"x($c{$_}/$c{$s[0]}*$f)."| $_ "foreach@s[0..21];

Note that this version normalizes for case. This doesn't shorten the solution any, since removing ,lc (for lower-casing) requires you to add A-Z to the split regex, so it's a wash.

If you're on a system where a newline is one character and not two, you can shorten this by another two chars by using a literal newline in place of \n. However, I haven't written the above sample that way, since it's "clearer" (ha!) that way.

Here is a mostly correct, but not remotely short enough, perl solution:

use strict;
use warnings;

my %short = map { $_ => 1 } qw/the and of to a i it in or is/;
my %count = ();

$count{$_}++ foreach grep { $_ && !$short{$_} } map { split /[^a-zA-Z]/ } (<>);
my @sorted = (sort { $count{$b} <=> $count{$a} } keys %count)[0..21];
my $widest = 76 - (length $sorted[0]);

print " " . ("_" x $widest) . "\n";
foreach (@sorted)
{
    my $width = int(($count{$_} / $count{$sorted[0]}) * $widest);
    print "|" . ("_" x $width) . "| $_ \n";
}

The following is about as short as it can get while remaining relatively readable. (392 chars).

%short = map { $_ => 1 } qw/the and of to a i it in or is/;
%count;

$count{$_}++ foreach grep { $_ && !$short{$_} } map { split /[^a-z]/, lc } (<>);
@sorted = (sort { $count{$b} <=> $count{$a} } keys %count)[0..21];
$widest = 76 - (length $sorted[0]);

print " " . "_" x $widest . "\n";
print"|" . "_" x int(($count{$_} / $count{$sorted[0]}) * $widest) . "| $_ \n" foreach @sorted;

Windows PowerShell, 199 chars

$x=$input-split'\P{L}'-notmatch'^(the|and|of|to|.?|i[tns]|or)$'|group|sort *
filter f($w){' '+'_'*$w
$x[-1..-22]|%{"|$('_'*($w*$_.Count/$x[-1].Count))| "+$_.Name}}
f(76..1|?{!((f $_)-match'.'*80)})[0]

(The last line break isn't necessary, but included here for readability.)

(Current code and my test files available in my SVN repository ^[1]. I hope my test cases catch most common errors (bar length, problems with regex matching and a few others))

Assumptions:

• US ASCII as input. It probably gets weird with Unicode.
• At least two non-stop words in the text

History ^[2]

Relaxed version (137), since that's counted separately by now, apparently:

($x=$input-split'\P{L}'-notmatch'^(the|and|of|to|.?|i[tns]|or)$'|group|sort *)[-1..-22]|%{"|$('_'*(76*$_.Count/$x[-1].Count))| "+$_.Name}

• doesn't close the first bar
• doesn't account for word length of non-first word

Variations of the bar lengths of one character compared to other solutions is due to PowerShell using rounding instead of truncation when converting floating-point numbers into integers. Since the task required only proportional bar length this should be fine, though.

Compared to other solutions I took a slightly different approach in determining the longest bar length by simply trying out and taking the highest such length where no line is longer than 80 characters.

An older version explained can be found here ^[3].

Ruby, 215, 216, 218, 221, 224, 236, 237 chars

update 1: Hurray! It's a tie with JS Bangs ^[1]' solution ^[2]. Can't think of a way to cut down any more :)

update 2: Played a dirty golf trick. Changed each to map to save 1 character :)

update 3: Changed File.read to IO.read +2. Array.group_by wasn't very fruitful, changed to reduce +6. Case insensitive check is not needed after lower casing with downcase in regex +1. Sorting in descending order is easily done by negating the value +6. Total savings +15

update 4: [0] rather than .first, +3. (@Shtééf)

update 5: Expand variable l in-place, +1. Expand variable s in-place, +2. (@Shtééf)

update 6: Use string addition rather than interpolation for the first line, +2. (@Shtééf)

w=(IO.read($_).downcase.scan(/[a-z]+/)-%w{the and of to a i it in or is}).reduce(Hash.new 0){|m,o|m[o]+=1;m}.sort_by{|k,v|-v}.take 22;m=76-w[0][0].size;puts' '+'_'*m;w.map{|x,f|puts"|#{'_'*(f*1.0/w[0][1]*m)}| #{x} "}

update 7: I went through a whole lot of hoopla to detect the first iteration inside the loop, using instance variables. All I got is +1, though perhaps there is potential. Preserving the previous version, because I believe this one is black magic. (@Shtééf)

(IO.read($_).downcase.scan(/[a-z]+/)-%w{the and of to a i it in or is}).reduce(Hash.new 0){|m,o|m[o]+=1;m}.sort_by{|k,v|-v}.take(22).map{|x,f|@f||(@f=f;puts' '+'_'*(@m=76-x.size));puts"|#{'_'*(f*1.0/@f*@m)}| #{x} "}

Readable version

string = File.read($_).downcase

words = string.scan(/[a-z]+/i)
allowed_words = words - %w{the and of to a i it in or is}
sorted_words = allowed_words.group_by{ |x| x }.map{ |x,y| [x, y.size] }.sort{ |a,b| b[1] <=> a[1] }.take(22)
highest_frequency = sorted_words.first
highest_frequency_count = highest_frequency[1]
highest_frequency_word = highest_frequency[0]

word_length = highest_frequency_word.size
widest = 76 - word_length

puts " #{'_' * widest}"    
sorted_words.each do |word, freq|
  width = (freq * 1.0 / highest_frequency_count) * widest
  puts "|#{'_' * width}| #{word} "
end

To use:

echo "Alice.txt" | ruby -ln GolfedWordFrequencies.rb

Output:

 _________________________________________________________________________
|_________________________________________________________________________| she 
|_______________________________________________________________| you 
|____________________________________________________________| said 
|_____________________________________________________| alice 
|_______________________________________________| was 
|___________________________________________| that 
|____________________________________| as 
|________________________________| her 
|_____________________________| with 
|_____________________________| at 
|____________________________| s 
|____________________________| t 
|__________________________| on 
|__________________________| all 
|_______________________| this 
|_______________________| for 
|_______________________| had 
|_______________________| but 
|______________________| be 
|_____________________| not 
|____________________| they 
|____________________| so 

Python 2.x, latitudinarian approach = 227 183 chars

import sys,re
t=re.split('\W+',sys.stdin.read().lower())
r=sorted((-t.count(w),w)for w in set(t)if w not in'andithetoforinis')[:22]
for l,w in r:print(78-len(r[0][1]))*l/r[0][0]*'=',w

Allowing for freedom in the implementation, I constructed a string concatenation that contains all the words requested for exclusion (the, and, of, to, a, i, it, in, or, is) - plus it also excludes the two infamous "words" s and t from the example - and I threw in for free the exclusion for an, for, he. I tried all concatenations of those words against corpus of the words from Alice, King James' Bible and the Jargon file to see if there are any words that will be mis-excluded by the string. And that is how I ended with two exclusion strings:itheandtoforinis and andithetoforinis.

PS. borrowed from other solutions to shorten the code.

=========================================================================== she 
================================================================= you
============================================================== said
====================================================== alice
================================================ was
============================================ that
===================================== as
================================= her
============================== at
============================== with
=========================== on
=========================== all
======================== this
======================== had
======================= but
====================== be
====================== not
===================== they
==================== so
=================== very
=================== what
================= little

Rant

Regarding words to ignore, one would think those would be taken from list of the most used words in English. That list depends on the text corpus ^[1] used. Per one of the most popular lists (http://en.wikipedia.org/wiki/Most_common_words_in_English, http://www.english-for-students.com/Frequently-Used-Words.html, http://www.sporcle.com/games/common_english_words.php), top 10 words are: the be(am/are/is/was/were) to of and a in that have I

The top 10 words from the Alice in Wonderland text are the and to a of it she i you said
The top 10 words from the Jargon File (v4.4.7) are the a of to and in is that or for

So question is why or was included in the problem's ignore list, where it's ~30th in popularity when the word that (8th most used) is not. etc, etc. Hence I believe the ignore list should be provided dynamically (or could be omitted).

Alternative idea would be simply to skip the top 10 words from the result - which actually would shorten the solution (elementary - have to show only the 11th to 32nd entries).

Python 2.x, punctilious approach = 277 243 chars

The chart drawn in the above code is simplified (using only one character for the bars). If one wants to reproduce exactly the chart from the problem description (which was not required), this code will do it:

import sys,re
t=re.split('\W+',sys.stdin.read().lower())
r=sorted((-t.count(w),w)for w in set(t)-set(sys.argv))[:22]
h=min(9*l/(77-len(w))for l,w in r)
print'',9*r[0][0]/h*'_'
for l,w in r:print'|'+9*l/h*'_'+'|',w

I take an issue with the somewhat random choice of the 10 words to exclude the, and, of, to, a, i, it, in, or, is so those are to be passed as command line parameters, like so:
python WordFrequencyChart.py the and of to a i it in or is <"Alice's Adventures in Wonderland.txt"

This is 213 chars + 30 if we account for the "original" ignore list passed on command line = 243

PS. The second code also does "adjustment" for the lengths of all top words, so none of them will overflow in degenerate case.

 _______________________________________________________________
|_______________________________________________________________| she
|_______________________________________________________| superlongstringstring
|_____________________________________________________| said
|______________________________________________| alice
|_________________________________________| was
|______________________________________| that
|_______________________________| as
|____________________________| her
|__________________________| at
|__________________________| with
|_________________________| s
|_________________________| t
|_______________________| on
|_______________________| all
|____________________| this
|____________________| for
|____________________| had
|____________________| but
|___________________| be
|___________________| not
|_________________| they
|_________________| so

Haskell - 366 351 344 337 333 characters

(One line break in main added for readability, and no line break needed at end of last line.)

import Data.List
import Data.Char
l=length
t=filter
m=map
f c|isAlpha c=toLower c|0<1=' '
h w=(-l w,head w)
x!(q,w)='|':replicate(minimum$m(q?)x)'_'++"| "++w
q?(g,w)=q*(77-l w)`div`g
b x=m(x!)x
a(l:r)=(' ':t(=='_')l):l:r
main=interact$unlines.a.b.take 22.sort.m h.group.sort
  .t(`notElem`words"the and of to a i it in or is").words.m f

How it works is best seen by reading the argument to interact backwards:

• map f lowercases alphabetics, replaces everything else with spaces.
• words produces a list of words, dropping the separating whitespace.
• filter (notElemwords "the and of to a i it in or is") discards all entries with forbidden words.
• group . sort sorts the words, and groups identical ones into lists.
• map h maps each list of identical words to a tuple of the form (-frequency, word).
• take 22 . sort sorts the tuples by descending frequency (the first tuple entry), and keeps only the first 22 tuples.
• b maps tuples to bars (see below).
• a prepends the first line of underscores, to complete the topmost bar.
• unlines joins all these lines together with newlines.

The tricky bit is getting the bar length right. I assumed that only underscores counted towards the length of the bar, so || would be a bar of zero length. The function b maps c x over x, where x is the list of histograms. The entire list is passed to c, so that each invocation of c can compute the scale factor for itself by calling u. In this way, I avoid using floating-point math or rationals, whose conversion functions and imports would eat many characters.

Note the trick of using -frequency. This removes the need to reverse the sort since sorting (ascending) -frequency will places the words with the largest frequency first. Later, in the function u, two -frequency values are multiplied, which will cancel the negation out.

JavaScript 1.8 (SpiderMonkey) - 354

x={};p='|';e=' ';z=[];c=77
while(l=readline())l.toLowerCase().replace(/\b(?!(the|and|of|to|a|i[tns]?|or)\b)\w+/g,function(y)x[y]?x[y].c++:z.push(x[y]={w:y,c:1}))
z=z.sort(function(a,b)b.c-a.c).slice(0,22)
for each(v in z){v.r=v.c/z[0].c
c=c>(l=(77-v.w.length)/v.r)?l:c}for(k in z){v=z[k]
s=Array(v.r*c|0).join('_')
if(!+k)print(e+s+e)
print(p+s+p+e+v.w)}

Sadly, the for([k,v]in z) from the Rhino version doesn't seem to want to work in SpiderMonkey, and readFile() is a little easier than using readline() but moving up to 1.8 allows us to use function closures to cut a few more lines....

Adding whitespace for readability:

x={};p='|';e=' ';z=[];c=77
while(l=readline())
  l.toLowerCase().replace(/\b(?!(the|and|of|to|a|i[tns]?|or)\b)\w+/g,
   function(y) x[y] ? x[y].c++ : z.push( x[y] = {w: y, c: 1} )
  )
z=z.sort(function(a,b) b.c - a.c).slice(0,22)
for each(v in z){
  v.r=v.c/z[0].c
  c=c>(l=(77-v.w.length)/v.r)?l:c
}
for(k in z){
  v=z[k]
  s=Array(v.r*c|0).join('_')
  if(!+k)print(e+s+e)
  print(p+s+p+e+v.w)
}

Usage: js golf.js < input.txt

Output:

 _________________________________________________________________________ 
|_________________________________________________________________________| she
|_______________________________________________________________| you
|____________________________________________________________| said
|____________________________________________________| alice
|______________________________________________| was
|___________________________________________| that
|___________________________________| as
|________________________________| her
|_____________________________| at
|_____________________________| with
|____________________________| s
|____________________________| t
|__________________________| on
|_________________________| all
|_______________________| this
|______________________| for
|______________________| had
|______________________| but
|_____________________| be
|_____________________| not
|___________________| they
|___________________| so

(base version - doesn't handle bar widths correctly)

JavaScript (Rhino) - 405 395 387 377 368 343 304 chars

I think my sorting logic is off, but.. I duno. Brainfart fixed.

Minified (abusing \n's interpreted as a ; sometimes):

x={};p='|';e=' ';z=[]
readFile(arguments[0]).toLowerCase().replace(/\b(?!(the|and|of|to|a|i[tns]?|or)\b)\w+/g,function(y){x[y]?x[y].c++:z.push(x[y]={w:y,c:1})})
z=z.sort(function(a,b){return b.c-a.c}).slice(0,22)
for([k,v]in z){s=Array((v.c/z[0].c)*70|0).join('_')
if(!+k)print(e+s+e)
print(p+s+p+e+v.w)}

perl, 205 191 189 characters/ 205 characters (fully implemented)

Some parts were inspired by the earlier perl/ruby submissions, a couple similar ideas were arrived at independently, the others are original. Shorter version also incorporates some things I saw/learned from other submissions.

Original:

$k{$_}++for grep{$_!~/^(the|and|of|to|a|i|it|in|or|is)$/}map{lc=~/[a-z]+/g}<>;@t=sort{$k{$b}<=>$k{$a}}keys%k;$l=76-length$t[0];printf" %s
",'_'x$l;printf"|%s| $_
",'_'x int$k{$_}/$k{$t[0]}*$l for@t[0..21];

Latest version down to 191 characters:

/^(the|and|of|to|.|i[tns]|or)$/||$k{$_}++for map{lc=~/[a-z]+/g}<>;@e=sort{$k{$b}<=>$k{$a}}keys%k;$n=" %s
";$r=(76-y///c)/$k{$_=$e[0]};map{printf$n,'_'x($k{$_}*$r),$_;$n="|%s| %s
"}@e[0,0..21]

Latest version down to 189 characters:

/^(the|and|of|to|.|i[tns]|or)$/||$k{$_}++for map{lc=~/[a-z]+/g}<>;@_=sort{$k{$b}<=>$k{$a}}keys%k;$n=" %s
";$r=(76-m//)/$k{$_=$_[0]};map{printf$n,'_'x($k{$_}*$r),$_;$n="|%s| %s
"}@_[0,0..21]

This version (205 char) accounts for the lines with words longer than what would be found later.

/^(the|and|of|to|.|i[tns]|or)$/||$k{$_}++for map{lc=~/[a-z]+/g}<>;($r)=sort{$a<=>$b}map{(76-y///c)/$k{$_}}@e=sort{$k{$b}<=>$k{$a}}keys%k;$n=" %s
";map{printf$n,'_'x($k{$_}*$r),$_;$n="|%s| %s
";}@e[0,0..21]

Python 3.1 - 245 229 charaters

I guess using Counter ^[1] is kind of cheating :) I just read about it about a week ago, so this was the perfect chance to see how it works.

import re,collections
o=collections.Counter([w for w in re.findall("[a-z]+",open("!").read().lower())if w not in"a and i in is it of or the to".split()]).most_common(22)
print('\n'.join('|'+76*v//o[0][1]*'_'+'| '+k for k,v in o))

Prints out:

|____________________________________________________________________________| she
|__________________________________________________________________| you
|_______________________________________________________________| said
|_______________________________________________________| alice
|_________________________________________________| was
|_____________________________________________| that
|_____________________________________| as
|__________________________________| her
|_______________________________| with
|_______________________________| at
|______________________________| s
|_____________________________| t
|____________________________| on
|___________________________| all
|________________________| this
|________________________| for
|________________________| had
|________________________| but
|______________________| be
|______________________| not
|_____________________| they
|____________________| so

Some of the code was "borrowed" from AKX's solution.

PHP CLI version (450 chars)

This solution takes into account the last requirement which most purists have conviniently chosen to ignore. That costed 170 characters!

Usage: php.exe <this.php> <file.txt>

Minified:

<?php $a=array_count_values(array_filter(preg_split('/[^a-z]/',strtolower(file_get_contents($argv[1])),-1,1),function($x){return !preg_match("/^(.|the|and|of|to|it|in|or|is)$/",$x);}));arsort($a);$a=array_slice($a,0,22);function R($a,$F,$B){$r=array();foreach($a as$x=>$f){$l=strlen($x);$r[$x]=$b=$f*$B/$F;if($l+$b>76)return R($a,$f,76-$l);}return$r;}$c=R($a,max($a),76-strlen(key($a)));foreach($a as$x=>$f)echo '|',str_repeat('-',$c[$x]),"| $x\n";?>

Human readable:

<?php

// Read:
$s = strtolower(file_get_contents($argv[1]));

// Split:
$a = preg_split('/[^a-z]/', $s, -1, PREG_SPLIT_NO_EMPTY);

// Remove unwanted words:
$a = array_filter($a, function($x){
       return !preg_match("/^(.|the|and|of|to|it|in|or|is)$/",$x);
     });

// Count:
$a = array_count_values($a);

// Sort:
arsort($a);

// Pick top 22:
$a=array_slice($a,0,22);


// Recursive function to adjust bar widths
// according to the last requirement:
function R($a,$F,$B){
    $r = array();
    foreach($a as $x=>$f){
        $l = strlen($x);
        $r[$x] = $b = $f * $B / $F;
        if ( $l + $b > 76 )
            return R($a,$f,76-$l);
    }
    return $r;
}

// Apply the function:
$c = R($a,max($a),76-strlen(key($a)));


// Output:
foreach ($a as $x => $f)
    echo '|',str_repeat('-',$c[$x]),"| $x\n";

?>

Output:

|-------------------------------------------------------------------------| she
|---------------------------------------------------------------| you
|------------------------------------------------------------| said
|-----------------------------------------------------| alice
|-----------------------------------------------| was
|-------------------------------------------| that
|------------------------------------| as
|--------------------------------| her
|-----------------------------| at
|-----------------------------| with
|--------------------------| on
|--------------------------| all
|-----------------------| this
|-----------------------| for
|-----------------------| had
|-----------------------| but
|----------------------| be
|---------------------| not
|--------------------| they
|--------------------| so
|-------------------| very
|------------------| what

When there is a long word, the bars are adjusted properly:

|--------------------------------------------------------| she
|---------------------------------------------------| thisisareallylongwordhere
|-------------------------------------------------| you
|-----------------------------------------------| said
|-----------------------------------------| alice
|------------------------------------| was
|---------------------------------| that
|---------------------------| as
|-------------------------| her
|-----------------------| with
|-----------------------| at
|--------------------| on
|--------------------| all
|------------------| this
|------------------| for
|------------------| had
|-----------------| but
|-----------------| be
|----------------| not
|---------------| they
|---------------| so
|--------------| very

Perl: 203 202 201 198 195 208 203 / 231 chars

$/=\0;/^(the|and|of|to|.|i[tns]|or)$/i||$x{lc$_}++for<>=~/[a-z]+/gi;map{$z=$x{$_};$y||{$y=(76-y///c)/$z}&&warn" "."_"x($z*$y)."\n";printf"|%.78s\n","_"x($z*$y)."| $_"}(sort{$x{$b}<=>$x{$a}}keys%x)[0..21]

Alternate, full implementation including indicated behaviour (global bar-squishing) for the pathological case in which the secondary word is both popular and long enough to combine to over 80 chars (this implementation is 231 chars):

$/=\0;/^(the|and|of|to|.|i[tns]|or)$/i||$x{lc$_}++for<>=~/[a-z]+/gi;@e=(sort{$x{$b}<=>$x{$a}}keys%x)[0..21];for(@e){$p=(76-y///c)/$x{$_};($y&&$p>$y)||($y=$p)}warn" "."_"x($x{$e[0]}*$y)."\n";for(@e){warn"|"."_"x($x{$_}*$y)."| $_\n"}

The specification didn't state anywhere that this had to go to STDOUT, so I used perl's warn() instead of print - four characters saved there. Used map instead of foreach, but I feel like there could still be some more savings in the split(join()). Still, got it down to 203 - might sleep on it. At least Perl's now under the "shell, grep, tr, grep, sort, uniq, sort, head, perl" char count for now ;)

PS: Reddit says "Hi" ;)

Update: Removed join() in favour of assignment and implicit scalar conversion join. Down to 202. Also please note I have taken advantage of the optional "ignore 1-letter words" rule to shave 2 characters off, so bear in mind the frequency count will reflect this.

Update 2: Swapped out assignment and implicit join for killing $/ to get the file in one gulp using <> in the first place. Same size, but nastier. Swapped out if(!$y){} for $y||{}&&, saved 1 more char => 201.

Update 3: Took control of lowercasing early (lc<>) by moving lc out of the map block - Swapped out both regexes to no longer use /i option, as no longer needed. Swapped explicit conditional x?y:z construct for traditional perlgolf || implicit conditional construct - /^...$/i?1:$x{$}++ for /^...$/||$x{$}++ Saved three characters! => 198, broke the 200 barrier. Might sleep soon... perhaps.

Update 4: Sleep deprivation has made me insane. Well. More insane. Figuring that this only has to parse normal happy text files, I made it give up if it hits a null. Saved two characters. Replaced "length" with the 1-char shorter (and much more golfish) y///c - you hear me, GolfScript?? I'm coming for you!!! sob

Update 5: Sleep dep made me forget about the 22row limit and subsequent-line limiting. Back up to 208 with those handled. Not too bad, 13 characters to handle it isn't the end of the world. Played around with perl's regex inline eval, but having trouble getting it to both work and save chars... lol. Updated the example to match current output.

Update 6: Removed unneeded braces protecting (...)for, since the syntactic candy ++ allows shoving it up against the for happily. Thanks to input from Chas. Owens (reminding my tired brain), got the character class i[tns] solution in there. Back down to 203.

Update 7: Added second piece of work, full implementation of specs (including the full bar-squishing behaviour for secondary long-words, instead of truncation which most people are doing, based on the original spec without the pathological example case)

Examples:

 _________________________________________________________________________
|_________________________________________________________________________| she
|_______________________________________________________________| you
|____________________________________________________________| said
|_____________________________________________________| alice
|_______________________________________________| was
|___________________________________________| that
|____________________________________| as
|________________________________| her
|_____________________________| with
|_____________________________| at
|__________________________| on
|__________________________| all
|_______________________| this
|_______________________| for
|_______________________| had
|_______________________| but
|______________________| be
|_____________________| not
|____________________| they
|____________________| so
|___________________| very
|__________________| what

Alternative implementation in pathological case example:

 _______________________________________________________________
|_______________________________________________________________| she
|_______________________________________________________| superlongstringstring
|____________________________________________________| said
|______________________________________________| alice
|________________________________________| was
|_____________________________________| that
|_______________________________| as
|____________________________| her
|_________________________| with
|_________________________| at
|_______________________| on
|______________________| all
|____________________| this
|____________________| for
|____________________| had
|____________________| but
|___________________| be
|__________________| not
|_________________| they
|_________________| so
|________________| very
|________________| what

F#, 452 chars

Strightforward: get a sequence a of word-count pairs, find the best word-count-per-column multiplier k, then print results.

let a=
 stdin.ReadToEnd().Split(" .?!,\":;'\r\n".ToCharArray(),enum 1)
 |>Seq.map(fun s->s.ToLower())|>Seq.countBy id
 |>Seq.filter(fun(w,n)->not(set["the";"and";"of";"to";"a";"i";"it";"in";"or";"is"].Contains w))
 |>Seq.sortBy(fun(w,n)-> -n)|>Seq.take 22
let k=a|>Seq.map(fun(w,n)->float(78-w.Length)/float n)|>Seq.min
let u n=String.replicate(int(float(n)*k)-2)"_"
printfn" %s "(u(snd(Seq.nth 0 a)))
for(w,n)in a do printfn"|%s| %s "(u n)w

Example (I have different freq counts than you, unsure why):

% app.exe < Alice.txt

 _________________________________________________________________________
|_________________________________________________________________________| she
|_______________________________________________________________| you
|_____________________________________________________________| said
|_____________________________________________________| alice
|_______________________________________________| was
|___________________________________________| that
|___________________________________| as
|________________________________| her
|_____________________________| with
|_____________________________| at
|____________________________| t
|____________________________| s
|__________________________| on
|_________________________| all
|_______________________| this
|______________________| had
|______________________| for
|_____________________| but
|_____________________| be
|____________________| not
|___________________| they
|__________________| so

Python 2.6, 347 chars

import re
W,x={},"a and i in is it of or the to".split()
[W.__setitem__(w,W.get(w,0)-1)for w in re.findall("[a-z]+",file("11.txt").read().lower())if w not in x]
W=sorted(W.items(),key=lambda p:p[1])[:22]
bm=(76.-len(W[0][0]))/W[0][1]
U=lambda n:"_"*int(n*bm)
print "".join(("%s\n|%s| %s "%((""if i else" "+U(n)),U(n),w))for i,(w,n)in enumerate(W))

Output:

 _________________________________________________________________________
|_________________________________________________________________________| she 
|_______________________________________________________________| you 
|____________________________________________________________| said 
|_____________________________________________________| alice 
|_______________________________________________| was 
|___________________________________________| that 
|____________________________________| as 
|________________________________| her 
|_____________________________| with 
|_____________________________| at 
|____________________________| s 
|____________________________| t 
|__________________________| on 
|__________________________| all 
|_______________________| this 
|_______________________| for 
|_______________________| had 
|_______________________| but 
|______________________| be 
|_____________________| not 
|____________________| they 
|____________________| so 

Gawk -- 336 (originally 507) characters

(after fixing the output formatting; fixing the contractions thing; tweaking; tweaking again; removing a wholly unnecessary sorting step; tweaking yet again; and again (oops this one broke the formatting); tweak some more; taking up Matt's challenge I desperately tweak so more; found another place to save a few, but gave two back to fix the bar length bug)

Heh heh! I am momentarily ahead of [Matt's JavaScript][1] solution^{counter challenge! ;)} and [AKX's python][2].

The problem seems to call out for a language that implements native associative arrays, so of course I've chosen one with a horribly deficient set of operators on them. In particular, you cannot control the order in which awk offers up the elements of a hash map, so I repeatedly scan the whole map to find the currently most numerous item, print it and delete it from the array.

It is all terribly inefficient, with all the golfifcations I've made it has gotten to be pretty awful, as well.

Minified:

{gsub("[^a-zA-Z]"," ");for(;NF;NF--)a[tolower($NF)]++}
END{split("the and of to a i it in or is",b," ");
for(w in b)delete a[b[w]];d=1;for(w in a){e=a[w]/(78-length(w));if(e>d)d=e}
for(i=22;i;--i){e=0;for(w in a)if(a[w]>e)e=a[x=w];l=a[x]/d-2;
t=sprintf(sprintf("%%%dc",l)," ");gsub(" ","_",t);if(i==22)print" "t;
print"|"t"| "x;delete a[x]}}

line breaks for clarity only: they are not necessary and should not be counted.

Output:

$ gawk -f wordfreq.awk.min < 11.txt 
 _________________________________________________________________________
|_________________________________________________________________________| she
|_______________________________________________________________| you
|____________________________________________________________| said
|____________________________________________________| alice
|______________________________________________| was
|__________________________________________| that
|___________________________________| as
|_______________________________| her
|____________________________| with
|____________________________| at
|___________________________| s
|___________________________| t
|_________________________| on
|_________________________| all
|______________________| this
|______________________| for
|______________________| had
|_____________________| but
|____________________| be
|____________________| not
|___________________| they
|__________________| so
$ sed 's/you/superlongstring/gI' 11.txt | gawk -f wordfreq.awk.min
 ______________________________________________________________________
|______________________________________________________________________| she
|_____________________________________________________________| superlongstring
|__________________________________________________________| said
|__________________________________________________| alice
|____________________________________________| was
|_________________________________________| that
|_________________________________| as
|______________________________| her
|___________________________| with
|___________________________| at
|__________________________| s
|__________________________| t
|________________________| on
|________________________| all
|_____________________| this
|_____________________| for
|_____________________| had
|____________________| but
|___________________| be
|___________________| not
|__________________| they
|_________________| so

Readable; 633 characters (originally 949):

{
    gsub("[^a-zA-Z]"," ");
    for(;NF;NF--)
    a[tolower($NF)]++
}
END{
    # remove "short" words
    split("the and of to a i it in or is",b," ");
    for (w in b) 
    delete a[b[w]];
    # Find the bar ratio
    d=1;
    for (w in a) {
    e=a[w]/(78-length(w));
    if (e>d)
        d=e
    }
    # Print the entries highest count first
    for (i=22; i; --i){               
    # find the highest count
    e=0;
    for (w in a) 
        if (a[w]>e)
        e=a[x=w];
        # Print the bar
    l=a[x]/d-2;
    # make a string of "_" the right length
    t=sprintf(sprintf("%%%dc",l)," ");
    gsub(" ","_",t);
    if (i==22) print" "t;
    print"|"t"| "x;
    delete a[x]
    }
}

*sh (+curl), partial solution

This is incomplete, but for the hell of it, here's the word-frequency counting half of the problem in 192 bytes:

curl -s http://www.gutenberg.org/files/11/11.txt|sed -e 's@[^a-z]@\n@gi'|tr '[:upper:]' '[:lower:]'|egrep -v '(^[^a-z]*$|\b(the|and|of|to|a|i|it|in|or|is)\b)' |sort|uniq -c|sort -n|tail -n 22

Common LISP, 670 characters

I'm a LISP newbie, and this is an attempt using an hash table for counting (so probably not the most compact method).

(flet((r()(let((x(read-char t nil)))(and x(char-downcase x)))))(do((c(
make-hash-table :test 'equal))(w NIL)(x(r)(r))y)((not x)(maphash(lambda
(k v)(if(not(find k '("""the""and""of""to""a""i""it""in""or""is"):test
'equal))(push(cons k v)y)))c)(setf y(sort y #'> :key #'cdr))(setf y
(subseq y 0(min(length y)22)))(let((f(apply #'min(mapcar(lambda(x)(/(-
76.0(length(car x)))(cdr x)))y))))(flet((o(n)(dotimes(i(floor(* n f)))
(write-char #\_))))(write-char #\Space)(o(cdar y))(write-char #\Newline)
(dolist(x y)(write-char #\|)(o(cdr x))(format t "| ~a~%"(car x))))))
(cond((char<= #\a x #\z)(push x w))(t(incf(gethash(concatenate 'string(
reverse w))c 0))(setf w nil)))))

can be run on for example with cat alice.txt | clisp -C golf.lisp.

In readable form is

(flet ((r () (let ((x (read-char t nil)))
               (and x (char-downcase x)))))
  (do ((c (make-hash-table :test 'equal))  ; the word count map
       w y                                 ; current word and final word list
       (x (r) (r)))  ; iteration over all chars
       ((not x)

        ; make a list with (word . count) pairs removing stopwords
        (maphash (lambda (k v)
                   (if (not (find k '("" "the" "and" "of" "to"
                                      "a" "i" "it" "in" "or" "is")
                                  :test 'equal))
                       (push (cons k v) y)))
                 c)

        ; sort and truncate the list
        (setf y (sort y #'> :key #'cdr))
        (setf y (subseq y 0 (min (length y) 22)))

        ; find the scaling factor
        (let ((f (apply #'min
                        (mapcar (lambda (x) (/ (- 76.0 (length (car x)))
                                               (cdr x)))
                                y))))
          ; output
          (flet ((outx (n) (dotimes (i (floor (* n f))) (write-char #\_))))
             (write-char #\Space)
             (outx (cdar y))
             (write-char #\Newline)
             (dolist (x y)
               (write-char #\|)
               (outx (cdr x))
               (format t "| ~a~%" (car x))))))

       ; add alphabetic to current word, and bump word counter
       ; on non-alphabetic
       (cond
        ((char<= #\a x #\z)
         (push x w))
        (t
         (incf (gethash (concatenate 'string (reverse w)) c 0))
         (setf w nil)))))

C (828)

It looks alot like obfuscated code, and uses glib for string, list and hash. Char count with wc -m says 828 . It does not consider single-char words. To calculate the max length of the bar, it consider the longest possible word among all, not only the first 22. Is this a deviation from the spec?

It does not handle failures and it does not release used memory.

#include <glib.h>
#define S(X)g_string_##X
#define H(X)g_hash_table_##X
GHashTable*h;int m,w=0,z=0;y(const void*a,const void*b){int*A,*B;A=H(lookup)(h,a);B=H(lookup)(h,b);return*B-*A;}void p(void*d,void*u){int *v=H(lookup)(h,d);if(w<22){g_printf("|");*v=*v*(77-z)/m;while(--*v>=0)g_printf("=");g_printf("| %s\n",d);w++;}}main(c){int*v;GList*l;GString*s=S(new)(NULL);h=H(new)(g_str_hash,g_str_equal);char*n[]={"the","and","of","to","it","in","or","is"};while((c=getchar())!=-1){if(isalpha(c))S(append_c)(s,tolower(c));else{if(s->len>1){for(c=0;c<8;c++)if(!strcmp(s->str,n[c]))goto x;if((v=H(lookup)(h,s->str))!=NULL)++*v;else{z=MAX(z,s->len);v=g_malloc(sizeof(int));*v=1;H(insert)(h,g_strdup(s->str),v);}}x:S(truncate)(s,0);}}l=g_list_sort(H(get_keys)(h),y);m=*(int*)H(lookup)(h,g_list_first(l)->data);g_list_foreach(l,p,NULL);}

Perl, 185 char

200 (slightly broken) 199 197 195 193 187 185 characters. Last two newlines are significant. Complies with the spec.

map$X{+lc}+=!/^(.|the|and|to|i[nst]|o[rf])$/i,/[a-z]+/gfor<>;
$n=$n>($:=$X{$_}/(76-y+++c))?$n:$:for@w=(sort{$X{$b}-$X{$a}}%X)[0..21];
die map{$U='_'x($X{$_}/$n);" $U
"x!$z++,"|$U| $_
"}@w

First line loads counts of valid words into %X.

The second line computes minimum scaling factor so that all output lines will be <= 80 characters.

The third line (contains two newline characters) produces the output.

Java - 886 865 756 744 742 744 752 742 714 680 chars

• Updates before first 742: improved regex, removed superfluous parameterized types, removed superfluous whitespace.

• Update 742 > 744 chars: fixed the fixed-length hack. It's only dependent on the 1st word, not other words (yet). Found several places to shorten the code (\\s in regex replaced by and ArrayList replaced by Vector). I'm now looking for a short way to remove the Commons IO dependency and reading from stdin.

• Update 744 > 752 chars: I removed the commons dependency. It now reads from stdin. Paste the text in stdin and hit Ctrl+Z to get result.

• Update 752 > 742 chars: I removed public and a space, made classname 1 char instead of 2 and it's now ignoring one-letter words.

• Update 742 > 714 chars: Updated as per comments of Carl: removed redundant assignment (742 > 730), replaced m.containsKey(k) by m.get(k)!=null (730 > 728), introduced substringing of line (728 > 714).

• Update 714 > 680 chars: Updated as per comments of Rotsor: improved bar size calculation to remove unnecessary casting and improved split() to remove unnecessary replaceAll().

import java.util.*;class F{public static void main(String[]a)throws Exception{StringBuffer b=new StringBuffer();for(int c;(c=System.in.read())>0;b.append((char)c));final Map<String,Integer>m=new HashMap();for(String w:b.toString().toLowerCase().split("(\\b(.|the|and|of|to|i[tns]|or)\\b|\\W)+"))m.put(w,m.get(w)!=null?m.get(w)+1:1);List<String>l=new Vector(m.keySet());Collections.sort(l,new Comparator(){public int compare(Object l,Object r){return m.get(r)-m.get(l);}});int c=76-l.get(0).length();String s=new String(new char[c]).replace('\0','_');System.out.println(" "+s);for(String w:l.subList(0,22))System.out.println("|"+s.substring(0,m.get(w)*c/m.get(l.get(0)))+"| "+w);}}

More readable version:

import java.util.*;
class F{
 public static void main(String[]a)throws Exception{
  StringBuffer b=new StringBuffer();for(int c;(c=System.in.read())>0;b.append((char)c));
  final Map<String,Integer>m=new HashMap();for(String w:b.toString().toLowerCase().split("(\\b(.|the|and|of|to|i[tns]|or)\\b|\\W)+"))m.put(w,m.get(w)!=null?m.get(w)+1:1);
  List<String>l=new Vector(m.keySet());Collections.sort(l,new Comparator(){public int compare(Object l,Object r){return m.get(r)-m.get(l);}});
  int c=76-l.get(0).length();String s=new String(new char[c]).replace('\0','_');System.out.println(" "+s);
  for(String w:l.subList(0,22))System.out.println("|"+s.substring(0,m.get(w)*c/m.get(l.get(0)))+"| "+w);
 }
}

Output:

 _________________________________________________________________________
|_________________________________________________________________________| she
|_______________________________________________________________| you
|____________________________________________________________| said
|_____________________________________________________| alice
|_______________________________________________| was
|___________________________________________| that
|____________________________________| as
|________________________________| her
|_____________________________| with
|_____________________________| at
|__________________________| on
|__________________________| all
|_______________________| this
|_______________________| for
|_______________________| had
|_______________________| but
|______________________| be
|_____________________| not
|____________________| they
|____________________| so
|___________________| very
|__________________| what

It pretty sucks that Java doesn't have String#join() and closures ^[1] (yet).

Edit by Rotsor:

I have made several changes to your solution:

• Replaced List with a String[]
• Reused the 'args' argument instead of declaring my own String array. Also used it as an argument to .ToArray()
• Replaced StringBuffer with a String (yes, yes, terrible performance)
• Replaced Java sorting with a selection-sort with early halting (only first 22 elements have to be found)
• Aggregated some int declaration into a single statement
• Implemented the non-cheating algorithm finding the most limiting line of output. Implemented it without FP.
• Fixed the problem of the program crashing when there were less than 22 distinct words in the text
• Implemented a new algorithm of reading input, which is fast and only 9 characters longer than the slow one.

The condensed code is 688 711 684 characters long:

import java.util.*;class F{public static void main(String[]l)throws Exception{Map<String,Integer>m=new HashMap();String w="";int i=0,k=0,j=8,x,y,g=22;for(;(j=System.in.read())>0;w+=(char)j);for(String W:w.toLowerCase().split("(\\b(.|the|and|of|to|i[tns]|or)\\b|\\W)+"))m.put(W,m.get(W)!=null?m.get(W)+1:1);l=m.keySet().toArray(l);x=l.length;if(x<g)g=x;for(;i<g;++i)for(j=i;++j<x;)if(m.get(l[i])<m.get(l[j])){w=l[i];l[i]=l[j];l[j]=w;}for(;k<g;k++){x=76-l[k].length();y=m.get(l[k]);if(k<1||y*i>x*j){i=x;j=y;}}String s=new String(new char[m.get(l[0])*i/j]).replace('\0','_');System.out.println(" "+s);for(k=0;k<g;k++){w=l[k];System.out.println("|"+s.substring(0,m.get(w)*i/j)+"| "+w);}}}

The fast version (720 693 characters)

import java.util.*;class F{public static void main(String[]l)throws Exception{Map<String,Integer>m=new HashMap();String w="";int i=0,k=0,j=8,x,y,g=22;for(;j>0;){j=System.in.read();if(j>90)j-=32;if(j>64&j<91)w+=(char)j;else{if(!w.matches("^(|.|THE|AND|OF|TO|I[TNS]|OR)$"))m.put(w,m.get(w)!=null?m.get(w)+1:1);w="";}}l=m.keySet().toArray(l);x=l.length;if(x<g)g=x;for(;i<g;++i)for(j=i;++j<x;)if(m.get(l[i])<m.get(l[j])){w=l[i];l[i]=l[j];l[j]=w;}for(;k<g;k++){x=76-l[k].length();y=m.get(l[k]);if(k<1||y*i>x*j){i=x;j=y;}}String s=new String(new char[m.get(l[0])*i/j]).replace('\0','_');System.out.println(" "+s);for(k=0;k<g;k++){w=l[k];System.out.println("|"+s.substring(0,m.get(w)*i/j)+"| "+w);}}}

More readable version:

import java.util.*;class F{public static void main(String[]l)throws Exception{
    Map<String,Integer>m=new HashMap();String w="";
    int i=0,k=0,j=8,x,y,g=22;
    for(;j>0;){j=System.in.read();if(j>90)j-=32;if(j>64&j<91)w+=(char)j;else{
        if(!w.matches("^(|.|THE|AND|OF|TO|I[TNS]|OR)$"))m.put(w,m.get(w)!=null?m.get(w)+1:1);w="";
    }}
    l=m.keySet().toArray(l);x=l.length;if(x<g)g=x;
    for(;i<g;++i)for(j=i;++j<x;)if(m.get(l[i])<m.get(l[j])){w=l[i];l[i]=l[j];l[j]=w;}
    for(;k<g;k++){x=76-l[k].length();y=m.get(l[k]);if(k<1||y*i>x*j){i=x;j=y;}}
    String s=new String(new char[m.get(l[0])*i/j]).replace('\0','_');
    System.out.println(" "+s);
    for(k=0;k<g;k++){w=l[k];System.out.println("|"+s.substring(0,m.get(w)*i/j)+"| "+w);}}
}

The version without behaviour improvements is 615 characters:

import java.util.*;class F{public static void main(String[]l)throws Exception{Map<String,Integer>m=new HashMap();String w="";int i=0,k=0,j=8,g=22;for(;j>0;){j=System.in.read();if(j>90)j-=32;if(j>64&j<91)w+=(char)j;else{if(!w.matches("^(|.|THE|AND|OF|TO|I[TNS]|OR)$"))m.put(w,m.get(w)!=null?m.get(w)+1:1);w="";}}l=m.keySet().toArray(l);for(;i<g;++i)for(j=i;++j<l.length;)if(m.get(l[i])<m.get(l[j])){w=l[i];l[i]=l[j];l[j]=w;}i=76-l[0].length();String s=new String(new char[i]).replace('\0','_');System.out.println(" "+s);for(k=0;k<g;k++){w=l[k];System.out.println("|"+s.substring(0,m.get(w)*i/m.get(l[0]))+"| "+w);}}}

Scala, 368 chars

First, a legible version in 592 characters:

object Alice {
  def main(args:Array[String]) {
    val s = io.Source.fromFile(args(0))
    val words = s.getLines.flatMap("(?i)\\w+\\b(?<!\\bthe|and|of|to|a|i|it|in|or|is)".r.findAllIn(_)).map(_.toLowerCase)
    val freqs = words.foldLeft(Map[String, Int]())((countmap, word)  => countmap + (word -> (countmap.getOrElse(word, 0)+1)))
    val sortedFreqs = freqs.toList.sort((a, b)  => a._2 > b._2)
    val top22 = sortedFreqs.take(22)
    val highestWord = top22.head._1
    val highestCount = top22.head._2
    val widest = 76 - highestWord.length
    println(" " + "_" * widest)
    top22.foreach(t => {
      val width = Math.round((t._2 * 1.0 / highestCount) * widest).toInt
      println("|" + "_" * width + "| " + t._1)
    })
  }
}

The console output looks like this:

$ scalac alice.scala 
$ scala Alice aliceinwonderland.txt
 _________________________________________________________________________
|_________________________________________________________________________| she
|_______________________________________________________________| you
|_____________________________________________________________| said
|_____________________________________________________| alice
|_______________________________________________| was
|____________________________________________| that
|____________________________________| as
|_________________________________| her
|______________________________| at
|______________________________| with
|_____________________________| s
|_____________________________| t
|___________________________| on
|__________________________| all
|_______________________| had
|_______________________| but
|______________________| be
|______________________| not
|____________________| they
|____________________| so
|___________________| very
|___________________| what

We can do some aggressive minifying and get it down to 415 characters:

object A{def main(args:Array[String]){val l=io.Source.fromFile(args(0)).getLines.flatMap("(?i)\\w+\\b(?<!\\bthe|and|of|to|a|i|it|in|or|is)".r.findAllIn(_)).map(_.toLowerCase).foldLeft(Map[String, Int]())((c,w)=>c+(w->(c.getOrElse(w,0)+1))).toList.sort((a,b)=>a._2>b._2).take(22);println(" "+"_"*(76-l.head._1.length));l.foreach(t=>println("|"+"_"*Math.round((t._2*1.0/l.head._2)*(76-l.head._1.length)).toInt+"| "+t._1))}}

The console session looks like this:

$ scalac a.scala 
$ scala A aliceinwonderland.txt
 _________________________________________________________________________
|_________________________________________________________________________| she
|_______________________________________________________________| you
|_____________________________________________________________| said
|_____________________________________________________| alice
|_______________________________________________| was
|____________________________________________| that
|____________________________________| as
|_________________________________| her
|______________________________| at
|______________________________| with
|_____________________________| s
|_____________________________| t
|___________________________| on
|__________________________| all
|_______________________| had
|_______________________| but
|______________________| be
|______________________| not
|____________________| they
|____________________| so
|___________________| very
|___________________| what

I'm sure a Scala expert could do even better.

Update: In the comments Thomas gave an even shorter version, at 368 characters:

object A{def main(a:Array[String]){val t=(Map[String, Int]()/:(for(x<-io.Source.fromFile(a(0)).getLines;y<-"(?i)\\w+\\b(?<!\\bthe|and|of|to|a|i|it|in|or|is)".r findAllIn x) yield y.toLowerCase).toList)((c,x)=>c+(x->(c.getOrElse(x,0)+1))).toList.sortBy(_._2).reverse.take(22);val w=76-t.head._1.length;print(" "+"_"*w);t map (s=>"\n|"+"_"*(s._2*w/t.head._2)+"| "+s._1) foreach print}}

Legibly, at 375 characters:

object Alice {
  def main(a:Array[String]) {
    val t = (Map[String, Int]() /: (
      for (
        x <- io.Source.fromFile(a(0)).getLines
        y <- "(?i)\\w+\\b(?<!\\bthe|and|of|to|a|i|it|in|or|is)".r.findAllIn(x)
      ) yield y.toLowerCase
    ).toList)((c, x) => c + (x -> (c.getOrElse(x, 0) + 1))).toList.sortBy(_._2).reverse.take(22)
    val w = 76 - t.head._1.length
    print (" "+"_"*w)
    t.map(s => "\n|" + "_" * (s._2 * w / t.head._2) + "| " + s._1).foreach(print)
  }
}

Scala 2.8, 311 314 320 330 332 336 341 375 characters

including long word adjustment. Ideas borrowed from the other solutions.

Now as a script (a.scala):

val t="\\w+\\b(?<!\\bthe|and|of|to|a|i[tns]?|or)".r.findAllIn(io.Source.fromFile(argv(0)).mkString.toLowerCase).toSeq.groupBy(w=>w).mapValues(_.size).toSeq.sortBy(-_._2)take 22
def b(p:Int)="_"*(p*(for((w,c)<-t)yield(76.0-w.size)/c).min).toInt
println(" "+b(t(0)._2))
for(p<-t)printf("|%s| %s \n",b(p._2),p._1)

Run with

scala -howtorun:script a.scala alice.txt

BTW, the edit from 314 to 311 characters actually removes only 1 character. Someone got the counting wrong before (Windows CRs?).

Clojure 282 strict

(let[[[_ m]:as s](->>(slurp *in*).toLowerCase(re-seq #"\w+\b(?<!\bthe|and|of|to|a|i[tns]?|or)")frequencies(sort-by val >)(take 22))[b](sort(map #(/(- 76(count(key %)))(val %))s))p #(do(print %1)(dotimes[_(* b %2)](print \_))(apply println %&))](p " " m)(doseq[[k v]s](p \| v \| k)))

Somewhat more legibly:

(let[[[_ m]:as s](->> (slurp *in*)
                   .toLowerCase
                   (re-seq #"\w+\b(?<!\bthe|and|of|to|a|i[tns]?|or)")
                   frequencies
                   (sort-by val >)
                   (take 22))
     [b] (sort (map #(/ (- 76 (count (key %)))(val %)) s))
     p #(do
          (print %1)
          (dotimes[_(* b %2)] (print \_))
          (apply println %&))]
  (p " " m)
  (doseq[[k v] s] (p \| v \| k)))

Java - 896 chars

931 chars

1233 chars made unreadable

1977 chars "uncompressed"

Update: I have aggressively reduced the character count. Omits single-letter words per updated spec.

I envy C# and LINQ so much.

import java.util.*;import java.io.*;import static java.util.regex.Pattern.*;class g{public static void main(String[] a)throws Exception{PrintStream o=System.out;Map<String,Integer> w=new HashMap();Scanner s=new Scanner(new File(a[0])).useDelimiter(compile("[^a-z]+|\\b(the|and|of|to|.|it|in|or|is)\\b",2));while(s.hasNext()){String z=s.next().trim().toLowerCase();if(z.equals(""))continue;w.put(z,(w.get(z)==null?0:w.get(z))+1);}List<Integer> v=new Vector(w.values());Collections.sort(v);List<String> q=new Vector();int i,m;i=m=v.size()-1;while(q.size()<22){for(String t:w.keySet())if(!q.contains(t)&&w.get(t).equals(v.get(i)))q.add(t);i--;}int r=80-q.get(0).length()-4;String l=String.format("%1$0"+r+"d",0).replace("0","_");o.println(" "+l);o.println("|"+l+"| "+q.get(0)+" ");for(i=m-1;i>m-22;i--){o.println("|"+l.substring(0,(int)Math.round(r*(v.get(i)*1.0)/v.get(m)))+"| "+q.get(m-i)+" ");}}}

"Readable":

import java.util.*;
import java.io.*;
import static java.util.regex.Pattern.*;
class g
{
   public static void main(String[] a)throws Exception
      {
      PrintStream o = System.out;
      Map<String,Integer> w = new HashMap();
      Scanner s = new Scanner(new File(a[0]))
         .useDelimiter(compile("[^a-z]+|\\b(the|and|of|to|.|it|in|or|is)\\b",2));
      while(s.hasNext())
      {
         String z = s.next().trim().toLowerCase();
         if(z.equals(""))
            continue;
         w.put(z,(w.get(z) == null?0:w.get(z))+1);
      }
      List<Integer> v = new Vector(w.values());
      Collections.sort(v);
      List<String> q = new Vector();
      int i,m;
      i = m = v.size()-1;
      while(q.size()<22)
      {
         for(String t:w.keySet())
            if(!q.contains(t)&&w.get(t).equals(v.get(i)))
               q.add(t);
         i--;
      }
      int r = 80-q.get(0).length()-4;
      String l = String.format("%1$0"+r+"d",0).replace("0","_");
      o.println(" "+l);
      o.println("|"+l+"| "+q.get(0)+" ");
      for(i = m-1; i > m-22; i--)
      {
         o.println("|"+l.substring(0,(int)Math.round(r*(v.get(i)*1.0)/v.get(m)))+"| "+q.get(m-i)+" ");
      }
   }
}

Output of Alice:

 _________________________________________________________________________
|_________________________________________________________________________| she
|_______________________________________________________________| you
|_____________________________________________________________| said
|_____________________________________________________| alice
|_______________________________________________| was
|____________________________________________| that
|____________________________________| as
|_________________________________| her
|______________________________| with
|______________________________| at
|___________________________| on
|__________________________| all
|________________________| this
|________________________| for
|_______________________| had
|_______________________| but
|______________________| be
|______________________| not
|____________________| they
|____________________| so
|___________________| very
|___________________| what

Output of Don Quixote (also from Gutenberg):

 ________________________________________________________________________
|________________________________________________________________________| that
|________________________________________________________| he
|______________________________________________| for
|__________________________________________| his
|________________________________________| as
|__________________________________| with
|_________________________________| not
|_________________________________| was
|________________________________| him
|______________________________| be
|___________________________| don
|_________________________| my
|_________________________| this
|_________________________| all
|_________________________| they
|________________________| said
|_______________________| have
|_______________________| me
|______________________| on
|______________________| so
|_____________________| you
|_____________________| quixote

C++, 647 chars

I don't expect to score highly by using C++, but nevermind that. I'm pretty sure it hits all the requirements. Note that I used the C++0x auto keyword for variable declaration, so adjust your complier appropriately if you decide to test my code.

Minimised version

#include <iostream>
#include <cstring>
#include <map>
using namespace std;
#define C string
#define S(x)v=F/a,cout<<#x<<C(v,'_')
#define F t->first
#define G t->second
#define O &&F!=
#define L for(i=22;i-->0;--t)
int main(){map<C,int>f;char d[230];int i=1,v;for(;i<256;i++)d[i<123?i-1:i-27]=i;d[229]=0;char w[99];while(cin>>w){for(i=0;w[i];i++)w[i]=tolower(w[i]);char*p=strtok(w,d);while(p)++f[p],p=strtok(0,d);}multimap<int,C>c;for(auto t=f.end();--t!=f.begin();)if(F!="the"O"and"O"of"O"to"O"a"O"i"O"it"O"in"O"or"O"is")c.insert(pair<int,C>(G,F));auto t=--c.end();float a=0,A;L A=F/(76.0-G.length()),a=a>A?a:A;t=--c.end();S( );L S(\n|)<<"| "<<G;}

Here's a second version that is more "C++" by using string, not char[] and strtok. It's a bit larger, at 669 (+22 vs above), but I can't get it smaller at the moment so thought I'd post it anyway.

#include <iostream>
#include <map>
using namespace std;
#define C string
#define S(x)v=F/a,cout<<#x<<C(v,'_')
#define F t->first
#define G t->second
#define O &&F!=
#define L for(i=22;i-->0;--t)
#define E e=w.find_first_of(d,g);g=w.find_first_not_of(d,e);
int main(){map<C,int>f;int i,v;C w,x,d="abcdefghijklmnopqrstuvwxyz";while(cin>>w){for(i=w.size();i-->0;)w[i]=tolower(w[i]);unsigned g=0,E while(g-e>0){x=w.substr(e,g-e),++f[x],E}}multimap<int,C>c;for(auto t=f.end();--t!=f.begin();)if(F!="the"O"and"O"of"O"to"O"a"O"i"O"it"O"in"O"or"O"is")c.insert(pair<int,C>(G,F));auto t=--c.end();float a=0,A;L A=F/(76.0-G.length()),a=a>A?a:A;t=--c.end();S( );L S(\n|)<<"| "<<G;}

I've removed the full version, because I can't be bothered to keep updating it with my tweaks to the minimised version. See edit history if you're interested in the (possibly outdated) long version.

Yet another python 2.x - 206 chars (or 232 with 'width bar')

I believe this one if fully compliant with the question. Ignore list is here, it fully checks for line length (see exemple where I replaced Alice by Aliceinwonderlandbylewiscarroll througout the text making the fifth item the longest line. Even the filename is provided from command line instead of hardcoded (hardcoding it would remove about 10 chars). It has one drawback (but I believe it's ok with the question) as it compute an integer divider to make line shorter than 80 chars, the longest line is shorter than 80 characters, not exactly 80 characters. The python 3.x version does not have this defect (but is way longer).

Also I believe it is not so hard to read.

import sys,re
t=re.split("\W+(?:(?:the|and|o[fr]|to|a|i[tns]?)\W+)*",sys.stdin.read().lower())
b=sorted((-t.count(x),x)for x in set(t))[:22]
for l,w in b:print"|"+l/min(z/(78-len(e))for z,e in b)*'-'+"|",w

|----------------------------------------------------------------| she
|--------------------------------------------------------| you
|-----------------------------------------------------| said
|----------------------------------------------| aliceinwonderlandbylewiscarroll
|-----------------------------------------| was
|--------------------------------------| that
|-------------------------------| as
|----------------------------| her
|--------------------------| at
|--------------------------| with
|-------------------------| s
|-------------------------| t
|-----------------------| on
|-----------------------| all
|---------------------| this
|--------------------| for
|--------------------| had
|--------------------| but
|-------------------| be
|-------------------| not
|------------------| they
|-----------------| so

As it is not clear if we must print the max bar alone on it's line (like in sample output). Below is another one that do it, but 232 chars.

import sys,re
t=re.split("\W+(?:(?:the|and|o[fr]|to|a|i[tns]?)\W+)*",sys.stdin.read().lower())
b=sorted((-t.count(x),x)for x in set(t))[:22]
f=min(z/(78-len(e))for z,e in b)
print"",b[0][0]/f*'-'
for y,w in b:print"|"+y/f*'-'+"|",w

Python 3.x - 256 chars

Using Counter class from python 3.x, there was high hopes to make it shorter (as Counter does everything that we need here). It comes out it's not better. Below is my trial 266 chars:

import sys,re,collections as c
b=c.Counter(re.split("\W+(?:(?:the|and|o[fr]|to|a|i[tns]?)\W+)*",
sys.stdin.read().lower())).most_common(22)
F=lambda p,x,w:print(p+'-'*int(x/max(z/(77.-len(e))for e,z in b))+w)
F(" ",b[0][1],"")
for w,y in b:F("|",y,"| "+w)

The problem is that collections and most_common are very long words and even Counter is not short... really, not using Counter makes code only 2 characters longer ;-(

python 3.x also introduce other constraints : dividing two integers is not an integer any more (so we have to cast to int), print is now a function (must add parenthesis), etc. That's why it comes out 22 characters longer than python2.x version, but way faster. Maybe some more experimented python 3.x coder will have ideas to shorten the code.

Java - 991 chars _{^{(incl newlines and indentations)}}

I took the code of @seanizer ^[1], fixed a bug (he omitted the 1st output line), made some improvements to make the code more 'golfy'.

import java.util.*;
import java.util.regex.*;
import org.apache.commons.io.IOUtils;
public class WF{
 public static void main(String[] a)throws Exception{
  String t=IOUtils.toString(new java.net.URL(a[0]).openStream());
  class W implements Comparable<W> {
   String w;int f=1;W(String W){w=W;}public int compareTo(W o){return o.f-f;}
   String d(float r){char[]c=new char[(int)(f/r)];Arrays.fill(c,'_');return "|"+new String(c)+"| "+w;}
  }
  Map<String,W>M=new HashMap<String,W>();
  Matcher m=Pattern.compile("\\b\\w+\\b").matcher(t.toLowerCase());
  while(m.find()){String w=m.group();W W=M.get(w);if(W==null)M.put(w,new W(w));else W.f++;}
  M.keySet().removeAll(Arrays.asList("the,and,of,to,a,i,it,in,or,is".split(",")));
  List<W>L=new ArrayList<W>(M.values());Collections.sort(L);int l=76-L.get(0).w.length();
  System.out.println(" "+new String(new char[l]).replace('\0','_'));
  for(W w:L.subList(0,22))System.out.println(w.d((float)L.get(0).f/(float)l));
 }
}

Output:

 _________________________________________________________________________
|_________________________________________________________________________| she
|_______________________________________________________________| you
|____________________________________________________________| said
|_____________________________________________________| alice
|_______________________________________________| was
|___________________________________________| that
|____________________________________| as
|________________________________| her
|_____________________________| with
|_____________________________| at
|____________________________| s
|____________________________| t
|__________________________| on
|__________________________| all
|_______________________| this
|_______________________| for
|_______________________| had
|_______________________| but
|______________________| be
|_____________________| not
|____________________| they
|____________________| so

R 449 chars

can probably get shorter...

bar <- function(w, l)
    {
    b <- rep("-", l)
    s <- rep(" ", l)
    cat(" ", b, "\n|", s, "| ", w, "\n ", b, "\n", sep="")
    }

f <- "alice.txt"
e <- c("the", "and", "of", "to", "a", "i", "it", "in", "or", "is", "")
w <- unlist(lapply(readLines(file(f)), strsplit, s=" "))
w <- tolower(w)
w <- unlist(lapply(w, gsub, pa="[^a-z]", r=""))
u <- unique(w[!w %in% e])
n <- unlist(lapply(u, function(x){length(w[w==x])}))
o <- rev(order(n))
n <- n[o]
m <- 77 - max(unlist(lapply(u[1:22], nchar)))
n <- floor(m*n/n[1])
u <- u[o]

for (i in 1:22)
    bar(u[i], n[i])

Groovy, 424 389 378 321 chars

replaced b=map.get(a) with b=map[a], replaced split with matcher / iterator

def r,s,m=[:],n=0;def p={println it};def w={"_".multiply it};(new URL(this.args[0]).text.toLowerCase()=~/\b\w+\b/).each{s=it;if(!(s==~/(the|and|of|to|a|i[tns]?|or)/))m[s]=m[s]==null?1:m[s]+1};m.keySet().sort{a,b->m[b]<=>m[a]}.subList(0,22).each{k->if(n++<1){r=(m[k]/(76-k.length()));p" "+w(m[k]/r)};p"|"+w(m[k]/r)+"|"+k}

(executed as groovy script with the URL as cmd line arg. No imports required!)

Readable version here:

def r,s,m=[:],n=0;
def p={println it};
def w={"_".multiply it};
(new URL(this.args[0]).text.toLowerCase()
        =~ /\b\w+\b/
        ).each{
        s=it;
        if (!(s ==~/(the|and|of|to|a|i[tns]?|or)/))
            m[s] = m[s] == null ? 1 : m[s] + 1
        };
    m.keySet()
        .sort{
            a,b -> m[b] <=> m[a]
        }
        .subList(0,22).each{
            k ->
                if( n++ < 1 ){
                    r=(m[k]/(76-k.length()));
                    p " " + w(m[k]/r)
                };
                p "|" + w(m[k]/r) + "|" + k
}

Python 2.6, 273 269 267 266 characters.

(Edit: Props to ChristopheD for character-shaving suggestions)

import sys,re
t=re.findall('[a-z]+',"".join(sys.stdin).lower())
d=sorted((t.count(w),w)for w in set(t)-set("the and of to a i it in or is".split()))[:-23:-1]
r=min((78.-len(m[1]))/m[0]for m in d)
print'','_'*(int(d[0][0]*r-2))
for(a,b)in d:print"|"+"_"*(int(a*r-2))+"|",b

Output:

 _________________________________________________________________________
|_________________________________________________________________________| she
|_______________________________________________________________| you
|____________________________________________________________| said
|____________________________________________________| alice
|______________________________________________| was
|__________________________________________| that
|___________________________________| as
|_______________________________| her
|____________________________| with
|____________________________| at
|___________________________| s
|___________________________| t
|_________________________| on
|_________________________| all
|______________________| this
|______________________| for
|______________________| had
|_____________________| but
|____________________| be
|____________________| not
|___________________| they
|__________________| so

MATLAB 335 404 410 bytes 357 bytes. 390 bytes.

The updated code is now 335 characters instead of 404, and seems to do well for both examples.

Original Message (For code of 404 characters)

This version is a bit longer, however, it will properly scale the length of the bars if there is a word that is ridiculously long so that none of the columns go over 80.

So, my code is 357 bytes without re-scaling, and 410 long with re-scaling.

A=textscan(fopen('11.txt'),'%s','delimiter',' 0123456789,.!?-_*^:;=+\\/(){}[]@&#$%~`|"''');
s=lower(A{1});s(cellfun('length', s)<2)=[];s(ismember(s,{'the','and','of','to','it','in','or','is'}))=[];
[w,~,i]=unique(s);N=hist(i,max(i)); [j,k]=sort(N,'descend'); b=k(1:22); n=cellfun('length',w(b));
q=80*N(b)'/N(k(1))+n; q=floor(q*78/max(q)-n); for i=1:22, fprintf('%s| %s\n',repmat('_',1,l(i)),w{k(i)});end

Results:

___________________________________________________________________________| she
_________________________________________________________________| you
______________________________________________________________| said
_______________________________________________________| alice
________________________________________________| was
____________________________________________| that
_____________________________________| as
_________________________________| her
______________________________| at
______________________________| with
____________________________| on
___________________________| all
_________________________| this
________________________| for
________________________| had
________________________| but
_______________________| be
_______________________| not
_____________________| they
____________________| so
___________________| very
___________________| what

For example, replacing all instances of "you" in the Alice in Wonderland text with "superlongstringofridiculousness", my code will correctly scale the results:

____________________________________________________________________| she
_________________________________________________________| superlongstringstring
________________________________________________________| said
_________________________________________________| alice
____________________________________________| was
________________________________________| that
_________________________________| as
______________________________| her
___________________________| with
___________________________| at
_________________________| on
________________________| all
_____________________| this
_____________________| for
_____________________| had
_____________________| but
____________________| be
____________________| not
__________________| they
__________________| so
_________________| very
_________________| what

Here is the updated code written a little bit more legibly:

A=textscan(fopen('t'),'%s','delimiter','':'@');
s=lower(A{1});
s(cellfun('length', s)<2|ismember(s,{'the','and','of','to','it','in','or','is'}))=[];
[w,~,i]=unique(s);
N=hist(i,max(i)); 
[j,k]=sort(N,'descend'); 
n=cellfun('length',w(k));
q=80*N(k)'/N(k(1))+n; 
q=floor(q*78/max(q)-n); 
for i=1:22, 
    fprintf('%s| %s\n',repmat('_',1,q(i)),w{k(i)});
end

Shell, 228 characters , with 80 chars constraint working

tr A-Z a-z|tr -Cs a-z "\n"|sort|egrep -v "^(the|and|of|to|a|i|it|in|or|is)$" |uniq -c|sort -r|head -22>g
n=1
while :
do
awk '{printf "|%0*s| %s\n",$1*'$n'/1e3,"",$2;}' g|tr 0 _>o 
egrep -q .{80} o&&break
n=$((n+1))
done
cat o

I'm surprised nobody seems to have used the amazing * feature of printf.

cat 11-very.txt > golf.sh

|__________________________________________________________________________| she
|________________________________________________________________| you
|_____________________________________________________________| said
|______________________________________________________| alice
|_______________________________________________| was
|____________________________________________| that
|____________________________________| as
|_________________________________| her
|______________________________| with
|______________________________| at
|_____________________________| s
|_____________________________| t
|___________________________| on
|__________________________| all
|________________________| this
|_______________________| for
|_______________________| had
|_______________________| but
|______________________| be
|______________________| not
|____________________| they
|____________________| so

cat 11 | golf.sh

|_________________________________________________________________| she
|_________________________________________________________| verylongstringstring
|______________________________________________________| said
|_______________________________________________| alice
|__________________________________________| was
|_______________________________________| that
|________________________________| as
|_____________________________| her
|___________________________| with
|___________________________| at
|__________________________| s
|_________________________| t
|________________________| on
|_______________________| all
|_____________________| this
|_____________________| for
|_____________________| had
|____________________| but
|___________________| be
|___________________| not
|__________________| they
|__________________| so

Scala, 327 characters

This was adapted from mkneissl's answer ^[1] inspired by a Python version, though it is bigger. I'm leaving it here in case someone can make it shorter.

val f="\\w+\\b(?<!\\bthe|and|of|to|a|i[tns]?|or)".r.findAllIn(io.Source.fromFile("11.txt").mkString.toLowerCase).toSeq
val t=f.toSet[String].map(x=> -f.count(x==)->x).toSeq.sorted take 22
def b(p:Int)="_"*(-p/(for((c,w)<-t)yield-c/(76.0-w.size)).max).toInt
println(" "+b(t(0)._1))
for(p<-t)printf("|%s| %s \n",b(p._1),p._2)

Clojure - 611 chars (not minimized)

I tried writing the code in as much idiomatic Clojure as I could so late in the night. I am not too proud of the draw-chart function, but I guess the code will speak volumes of the succinctness of Clojure.

(ns word-freq
(:require [clojure.contrib.io :as io]))

(defn word-freq
  [f]
  (take 22 (->> f
                io/read-lines ;;; slurp should work too, but I love map/red
                (mapcat (fn [l] (map #(.toLowerCase %) (re-seq #"\w+" l))))
                (remove #{"the" "and" "of" "to" "a" "i" "it" "in" "or" "is"})
                (reduce #(assoc %1 %2 (inc (%1 %2 0))) {})
                (sort-by (comp - val)))))

(defn draw-chart
  [fs]
  (let [[[w f] & _] fs]
    (apply str
           (interpose \newline
                      (map (fn [[k v]] (apply str (concat "|" (repeat (int (* (- 76 (count w)) (/ v f 1))) "_") "| " k " ")) ) fs)))))

;;; (println (draw-chart (word-freq "/Users/ghoseb/Desktop/alice.txt")))

Output:

|_________________________________________________________________________| she 
|_______________________________________________________________| you 
|____________________________________________________________| said 
|____________________________________________________| alice 
|_______________________________________________| was 
|___________________________________________| that 
|____________________________________| as 
|________________________________| her 
|_____________________________| with 
|_____________________________| at 
|____________________________| t 
|____________________________| s 
|__________________________| on 
|__________________________| all 
|_______________________| for 
|_______________________| had 
|_______________________| this 
|_______________________| but 
|______________________| be 
|_____________________| not 
|____________________| they 
|____________________| so

I know, this doesn't follow the spec, but hey, this is some very clean Clojure code which is already so small :)

Java, slowly getting shorter (1500 1358 1241 1020 913 890 chars)

stripped even more white space and var name length. removed generics where possible, removed inline class and try/catch block too bad, my 900 version had a bug

removed another try / catch block

import java.net.*;import java.util.*;import java.util.regex.*;import org.apache.commons.io.*;public class G{public static void main(String[]a)throws Exception{String text=IOUtils.toString(new URL(a[0]).openStream()).toLowerCase().replaceAll("\\b(the|and|of|to|a|i[tns]?|or)\\b","");final Map<String,Integer>p=new HashMap();Matcher m=Pattern.compile("\\b\\w+\\b").matcher(text);Integer b;while(m.find()){String w=m.group();b=p.get(w);p.put(w,b==null?1:b+1);}List<String>v=new Vector(p.keySet());Collections.sort(v,new Comparator(){public int compare(Object l,Object m){return p.get(m)-p.get(l);}});boolean t=true;float r=0;for(String w:v.subList(0,22)){if(t){t=false;r=p.get(w)/(float)(80-(w.length()+4));System.out.println(" "+new String(new char[(int)(p.get(w)/r)]).replace('\0','_'));}System.out.println("|"+new String(new char[(int)(((Integer)p.get(w))/r)]).replace('\0','_')+"|"+w);}}}

Readable version:

import java.net.*;
import java.util.*;
import java.util.regex.*;
import org.apache.commons.io.*;

public class G{

    public static void main(String[] a) throws Exception{
        String text =
            IOUtils.toString(new URL(a[0]).openStream())
                .toLowerCase()
                .replaceAll("\\b(the|and|of|to|a|i[tns]?|or)\\b", "");
        final Map<String, Integer> p = new HashMap();
        Matcher m = Pattern.compile("\\b\\w+\\b").matcher(text);
        Integer b;
        while(m.find()){
            String w = m.group();
            b = p.get(w);
            p.put(w, b == null ? 1 : b + 1);
        }
        List<String> v = new Vector(p.keySet());
        Collections.sort(v, new Comparator(){

            public int compare(Object l, Object m){
                return p.get(m) - p.get(l);
            }
        });
        boolean t = true;
        float r = 0;
        for(String w : v.subList(0, 22)){
            if(t){
                t = false;
                r = p.get(w) / (float) (80 - (w.length() + 4));
                System.out.println(" "
                    + new String(new char[(int) (p.get(w) / r)]).replace('\0',
                        '_'));
            }
            System.out.println("|"
                + new String(new char[(int) (((Integer) p.get(w)) / r)]).replace('\0',
                    '_') + "|" + w);
        }
    }
}

Javascript, 348 characters

After I finished mine, I stole some ideas from Matt :3

t=prompt().toLowerCase().replace(/\b(the|and|of|to|a|i[tns]?|or)\b/gm,'');r={};o=[];t.replace(/\b([a-z]+)\b/gm,function(a,w){r[w]?++r[w]:r[w]=1});for(i in r){o.push([i,r[i]])}m=o[0][1];o=o.slice(0,22);o.sort(function(F,D){return D[1]-F[1]});for(B in o){F=o[B];L=new Array(~~(F[1]/m*(76-F[0].length))).join('_');print(' '+L+'\n|'+L+'| '+F[0]+' \n')}

Requires print and prompt function support.

Gotta love the big ones...Objective-C (1070 931 905 chars)

#define S NSString
#define C countForObject
#define O objectAtIndex
#define U stringWithCString
main(int g,char**b){id c=[NSCountedSet set];S*d=[S stringWithContentsOfFile:[S U:b[1]]];id p=[NSPredicate predicateWithFormat:@"SELF MATCHES[cd]'(the|and|of|to|a|i[tns]?|or)|[^a-z]'"];[d enumerateSubstringsInRange:NSMakeRange(0,[d length])options:NSStringEnumerationByWords usingBlock:^(S*s,NSRange x,NSRange y,BOOL*z){if(![p evaluateWithObject:s])[c addObject:[s lowercaseString]];}];id s=[[c allObjects]sortedArrayUsingComparator:^(id a,id b){return(NSComparisonResult)([c C:b]-[c C:a]);}];g=[c C:[s O:0]];int j=76-[[s O:0]length];char*k=malloc(80);memset(k,'_',80);S*l=[S U:k length:80];printf(" %s\n",[[l substringToIndex:j]cString]),[[s subarrayWithRange:NSMakeRange(0,22)]enumerateObjectsUsingBlock:^(id a,NSUInteger x,BOOL*y){printf("|%s| %s\n",[[l substringToIndex:[c C:a]*j/g]cString],[a cString]);}];}

Switched to using a lot of depreciate APIs, removed some memory management that wasn't needed, more aggressive whitespace removal

 _________________________________________________________________________
|_________________________________________________________________________| she
|______________________________________________________________| said
|__________________________________________________________| you
|____________________________________________________| alice
|________________________________________________| was
|_______________________________________| that
|____________________________________| as
|_________________________________| her
|______________________________| with
|______________________________| at
|___________________________| on
|__________________________| all
|________________________| this
|________________________| for
|________________________| had
|_______________________| but
|______________________| be
|______________________| not
|____________________| so
|___________________| very
|__________________| what
|_________________| they

Python, 320 characters

import sys
i="the and of to a i it in or is".split()
d={}
for j in filter(lambda x:x not in i,sys.stdin.read().lower().split()):d[j]=d.get(j,0)+1
w=sorted(d.items(),key=lambda x:x[1])[:-23:-1]
m=sorted(dict(w).values())[-1]
print" %s\n"%("_"*(76-m)),"\n".join(map(lambda x:("|%s| "+x[0])%("_"*((76-m)*x[1]/w[0][1])),w))

R, 298 chars

f=scan("stdin","ch")
u=unlist
s=strsplit
a=u(s(u(s(tolower(f),"[^a-z]")),"^(the|and|of|to|it|in|or|is|.|)$"))
v=unique(a)
r=sort(sapply(v,function(i) sum(a==i)),T)[2:23]  #the first item is an empty string, just skipping it
w=names(r)
q=(78-max(nchar(w)))*r/max(r)
cat(" ",rep("_",q[1])," \n",sep="")
for(i in 1:22){cat("|",rep("_",q[i]),"| ",w[i],"\n",sep="")}

The output is:

 _________________________________________________________________________ 
|_________________________________________________________________________| she
|_______________________________________________________________| you
|____________________________________________________________| said
|_____________________________________________________| alice
|_______________________________________________| was
|___________________________________________| that
|____________________________________| as
|________________________________| her
|_____________________________| at
|_____________________________| with
|__________________________| on
|__________________________| all
|_______________________| this
|_______________________| for
|_______________________| had
|_______________________| but
|______________________| be
|_____________________| not
|____________________| they
|____________________| so
|___________________| very
|__________________| what

And if "you" is replaced by something longer:

 ____________________________________________________________ 
|____________________________________________________________| she
|____________________________________________________| veryverylongstring
|__________________________________________________| said
|___________________________________________| alice
|______________________________________| was
|___________________________________| that
|_____________________________| as
|__________________________| her
|________________________| at
|________________________| with
|______________________| on
|_____________________| all
|___________________| this
|___________________| for
|___________________| had
|__________________| but
|__________________| be
|__________________| not
|________________| they
|________________| so
|_______________| very
|_______________| what

Python 290, 255, 253

290 characters in python (text read from standard input)

import sys,re
c={}
for w in re.findall("[a-z]+",sys.stdin.read().lower()):c[w]=c.get(w,0)+1-(","+w+","in",a,i,the,and,of,to,it,in,or,is,")
r=sorted((-v,k)for k,v in c.items())[:22]
sf=max((76.0-len(k))/v for v,k in r)
print" "+"_"*int(r[0][0]*sf)
for v,k in r:print"|"+"_"*int(v*sf)+"| "+k

but... after reading other solutions I all of a sudden realized that efficiency was not a request; so this is another shorter and much slower one (255 characters)

import sys,re
w=re.findall("\w+",sys.stdin.read().lower())
r=sorted((-w.count(x),x)for x in set(w)-set("the and of to a i it in or is".split()))[:22]
f=max((76.-len(k))/v for v,k in r)
print" "+"_"*int(f*r[0][0])
for v,k in r:print"|"+"_"*int(f*v)+"| "+k

and after some more reading other solutions...

import sys,re
w=re.findall("\w+",sys.stdin.read().lower())
r=sorted((-w.count(x),x)for x in set(w)-set("the and of to a i it in or is".split()))[:22]
f=max((76.-len(k))/v for v,k in r)
print"","_"*int(f*r[0][0])
for v,k in r:print"|"+"_"*int(f*v)+"|",k

And now this solution is almost byte-per-byte identical to Astatine's one :-D

Object Rexx 4.0 with PC-Pipes

address rxpipe 'pipe (end ?) < Alice.txt',
   '|regex split /[^a-zA-Z]/', -- split at non alphbetic character
   '|locate 2',                -- discard words shorter that 2 char  
   '|xlate lower',             -- translate all words to lower case
   ,                           -- discard list words that match list
   '|regex not match /^(the||and||of||to||it||in||or||is)$/',
   '|l:lookup autoadd before count',  -- accumulate and count words
 '? l:',                       -- no master records to feed into lookup 
 '? l:',                       -- list of counted words comes here
   ,                           -- columns 1-10 hold count, 11-n hold word
   '|sort 1.10 d',             -- sort in desending order by count
   '|take 22',                 -- take first 22 records only
   '|array wordlist',          -- store into a rexx array
   '|count max',               -- get length of longest record 
   '|var maxword'              -- save into a rexx variable

parse value wordlist[1] with count 11 .  -- get frequency of first word
barunit = count % (76-(maxword-10))      -- frequency units per chart bar char

say ' '||copies('_', (count+barunit)%barunit)  -- first line of the chart
do cntwd over wordlist                    
  parse var cntwd count 11 word          -- get word frequency and the word
  say '|'||copies('_', (count+barunit)%barunit)||'| '||word||' '
end

 ________________________________________________________________________________
|________________________________________________________________________________| she
|_____________________________________________________________________| you
|___________________________________________________________________| said
|__________________________________________________________| alice
|____________________________________________________| was
|________________________________________________| that
|________________________________________| as
|____________________________________| her
|_________________________________| at
|_________________________________| with
|______________________________| on
|_____________________________| all
|__________________________| this
|__________________________| for
|__________________________| had
|__________________________| but
|________________________| be
|________________________| not
|_______________________| they
|______________________| so
|_____________________| very
|_____________________| what

Ruby, 205

This Ruby version handles "superlongstringstring". (The first two lines are almost identical to the previous Ruby programs.)

It must be run this way:

ruby -n0777 golf.rb Alice.txt

W=($_.upcase.scan(/\w+/)-%w(THE AND OF TO A I IT
IN OR IS)).group_by{|x|x}.map{|k,v|[-v.size,k]}.sort[0,22]
u=proc{|m|"_"*(W.map{|n,s|(76.0-s.size)/n}.max*m)}
puts" "+u[W[0][0]],W.map{|n,s|"|%s| "%u[n]+s}

The third line creates a closure or lambda that yields a correctly scaled string of underscores:

u = proc{|m|
  "_" *
    (W.map{|n,s| (76.0 - s.size)/n}.max * m)
}

.max is used instead of .min because the numbers are negative.

Bourne shell, 213/240 characters

Improving on the shell version posted earlier, I can get it down to 213 characters:

tr A-Z a-z|tr -Cs a-z \\n|sort|egrep -v '^(the|and|of|to|a|i|it|in|or|is)$'|uniq -c|sort -rn|sed 22q>g
n=1
>o
until egrep -q .{80} o
do
awk '{printf "|%0*d| %s\n",$1*'$n'/1e3,0,$2}' g|tr 0 _>o 
((n++))
done
cat o

In order to get the upper outline on the top bar, I had to expand it to 240 characters:

tr A-Z a-z|tr -Cs a-z \\n|sort|egrep -v "^(the|and|of|to|a|i|it|in|or|is)$"|uniq -c|sort -r|sed 1p\;22q>g
n=1
>o
until egrep -q .{80} o
do
awk '{printf "|%0*d| %s\n",$1*'$n'/1e3,0,NR==1?"":$2}' g|sed '1s,|, ,g'|tr 0 _>o 
((n++))
done
cat o

shell, grep, tr, grep, sort, uniq, sort, head, perl - 194 chars

Adding some -i flags may drop the overly long tr A-Z a-z| step; the spec said nothing about the case displayed, and uniq -ci drops any case differences.

egrep -oi [a-z]+|egrep -wiv 'the|and|o[fr]|to|a|i[tns]?'|sort|uniq -ci|sort -nr|head -22|perl -lape'($f,$w)=@F;$.>1or($q,$x)=($f,76-length$w);$b="_"x($f/$q*$x);$_="|$b| $w ";$.>1or$_=" $b\n$_"'

That's minus 11 for the tr plus 2 for the -i's compared to the original 206 chars.

edit: minus 3 for the \\b which can be left out as pattern matching will commence on a boundary anyway.

sort gives lower case first, and uniq -ci takes the first occurence, so the only real change in output will be that Alice retains her upper case initial.

Go, 613 chars, could probably be much smaller:

package main
import(r "regexp";. "bytes";. "io/ioutil";"os";st "strings";s "sort";. "container/vector")
type z struct{c int;w string}
func(e z)Less(o interface{})bool{return o.(z).c<e.c}
func main(){b,_:=ReadAll(os.Stdin);g:=r.MustCompile
c,m,x:=g("[A-Za-z]+").AllMatchesIter(b,0),map[string]int{},g("the|and|of|it|in|or|is|to")
for w:=range c{w=ToLower(w);if len(w)>1&&!x.Match(w){m[string(w)]++}}
o,y:=&Vector{},0
for k,v:=range m{o.Push(z{v,k});if v>y{y=v}}
s.Sort(o)
for i,v:=range *o{if i>21{break};x:=v.(z);c:=int(float(x.c)/float(y)*80)
u:=st.Repeat("_",c);if i<1{println(" "+u)};println("|"+u+"| "+x.w)}}

I feel so dirty.

perl, 188 characters

The perl version above (as well as any regexp splitting based version) can get a few bytes shorter by including the list of forbidden words as negative lookahead assertions, rather than as a separate list. Furthermore the trailing semicolon can be left out.

I also included some other suggestions (- instead of <=>, for/foreach, dropped "keys") to get to

$c{$_}++for grep{$_}map{lc=~/\b(?!(?:the|and|a|of|or|i[nts]?|to)\b)[a-z]+/g}<>;@s=sort{$c{$b}-$c{$a}}%c;$f=76-length$s[0];say$"."_"x$f;say"|"."_"x($c{$_}/$c{$s[0]}*$f)."| $_ "for@s[0..21]

I don't know perl, but I presume that the (?!(?:...)\b) may lose the ?: if the handling around it is fixed.

GNU Smalltalk (386)

I think it can be made a little bit shorter, but still no idea how.

|q s f m|q:=Bag new. f:=FileStream stdin. m:=0.[f atEnd]whileFalse:[s:=f nextLine.(s notNil)ifTrue:[(s tokenize:'\W+')do:[:i|(((i size)>1)&({'the'.'and'.'of'.'to'.'it'.'in'.'or'.'is'}includes:i)not)ifTrue:[q add:(i asLowercase)]. m:=m max:(i size)]]].(q:=q sortedByCount)from:1to:22 do:[:i|'|'display.((i key)*(77-m)//(q first key))timesRepeat:['='display].('| %1'%{i value})displayNl]

Lua solution: 478 characters.

t,u={},{}for l in io.lines()do
for w in l:gmatch("%a+")do
w=w:lower()if not(" the and of to a i it in or is "):find(" "..w.." ")then
t[w]=1+(t[w]or 0)end
end
end
for k,v in next,t do
u[#u+1]={k,v}end
table.sort(u,function(a,b)return a[2]>b[2]end)m,n=u[1][2],math.min(#u,22)for w=80,1,-1 do
s=""for i=1,n do
a,b=u[i][1],w*u[i][2]/m
if b+#a>=78 then s=nil break end
s2=("_"):rep(b)if i==1 then
s=s.." " ..s2.."\n"end
s=s.."|"..s2.."| "..a.."\n"end
if s then print(s)break end end

Readable version:

t,u={},{}
for line in io.lines() do
    for w in line:gmatch("%a+") do
        w = w:lower()
        if not (" the and of to a i it in or is "):find(" "..w.." ") then
            t[w] = 1 + (t[w] or 0)
        end
    end
end
for k, v in pairs(t) do
    u[#u+1]={k, v}
end

table.sort(u, function(a, b)
    return a[2] > b[2]
end)

local max = u[1][2]
local n = math.min(#u, 22)

for w = 80, 1, -1 do
    s=""
    for i = 1, n do
        f = u[i][2]
        word = u[i][1]
        width = w * f / max
        if width + #word >= 78 then
            s=nil
            break
        end
        s2=("_"):rep(width)
        if i==1 then
            s=s.." " .. s2 .."\n"
        end
        s=s.."|" .. s2 .. "| " .. word.."\n"
    end
    if s then
        print(s)
        break
    end
end

TCL 554 Strict

foreach w [regexp -all -inline {[a-z]+} [string tolower [read stdin]]] {if {[lsearch {the and of to it in or is a i} $w]>=0} {continue};if {[catch {incr Ws($w)}]} {set Ws($w) 1}}
set T [lrange [lsort -decreasing -stride 2 -index 1 -integer [array get Ws]] 0 43]
foreach {w c} $T {lappend L [string length $w];lappend C $c}
set N [tcl::mathfunc::max {*}$L]
set C [lsort -integer $C]
set M [lindex $C end]
puts " [string repeat _ [expr {int((76-$N) * [lindex $T 1] / $M)}]] "
foreach {w c} $T {puts "|[string repeat _ [expr {int((76-$N) * $c / $M)}]]| $w"}

Or, more legibly

foreach w [regexp -all -inline {[a-z]+} [string tolower [read stdin]]] {
    if {[lsearch {the and of to a i it in or is} $w] >= 0} { continue }
    if {[catch {incr words($w)}]} {
        set words($w) 1
    }
}
set topwords [lrange [lsort -decreasing -stride 2 -index 1 -integer [array get words]] 0 43]
foreach {word count} $topwords {
    lappend lengths [string length $word]
    lappend counts $count
}
set maxlength [lindex [lsort -integer $lengths] end]
set counts [lsort -integer $counts]
set mincount [lindex $counts 0].0
set maxcount [lindex $counts end].0
puts " [string repeat _ [expr {int((76-$maxlength) * [lindex $topwords 1] / $maxcount)}]] "
foreach {word count} $topwords {
    set barlength [expr {int((76-$maxlength) * $count / $maxcount)}]
    puts "|[string repeat _ $barlength]| $word"
}

Another T-SQL solution borrowing some ideas from Martin's solution ^[1] (min76- etc).

declare @ varchar(max),@w real,@j int;select s=@ into[ ]set @=(select*
from openrowset(bulk'a',single_blob)a)while @>''begin set @=stuff(@,1,
patindex('%[a-z]%',@)-1,'')+'.'set @j=patindex('%[^a-z]%',@)if @j>2insert[ ]
select lower(left(@,@j-1))set @=stuff(@,1,@j,'')end;select top(22)s,count(*)
c into # from[ ]where',the,and,of,to,it,in,or,is,'not like'%,'+s+',%'
group by s order by 2desc;select @w=min((76.-len(s))/c),@=' '+replicate(
'_',max(c)*@w)from #;select @=@+'
|'+replicate('_',c*@w)+'| '+s+' 'from #;print @

The entire solution should be on two lines (concatenate first 7), although you can cut, paste and run it as-is. Total characters = 507 (counting the line break as 1 if you save it in Unix format and execute using SQLCMD)

Assumptions:

1. There isn't a temp table #
2. There isn't a table named [ ]
3. The input is in the default system folder, e.g. C:\windows\system32\a
4. Your query window has 'set nocount on' active (prevent spurious "rows affected" msgs)

And to get onto the list of solutions (<500 char), here's the "relaxed" edition at 483 characters (No vertical bars / No top bar / No trailing space after word)

declare @ varchar(max),@w real,@j int;select s=@ into[ ]set @=(select*
from openrowset(bulk'b',single_blob)a)while @>''begin set @=stuff(@,1,
patindex('%[a-z]%',@)-1,'')+'.'set @j=patindex('%[^a-z]%',@)if @j>2insert[ ]
select lower(left(@,@j-1))set @=stuff(@,1,@j,'')end;select top(22)s,count(*)
c into # from[ ]where',the,and,of,to,it,in,or,is,'not like'%,'+s+',%'
group by s order by 2desc;select @w=min((78.-len(s))/c),@=''from #;select @=@+'
'+replicate('_',c*@w)+' '+s from #;print @

Readable version

declare @ varchar(max), @w real, @j int
select s=@ into[ ] -- shortcut to create table; use defined variable to specify column type
-- openrowset reads an entire file
set @=(select * from openrowset(bulk'a',single_blob) a) -- a bit shorter than naming 'BulkColumn'

while @>'' begin -- loop until input is empty
    set @=stuff(@,1,patindex('%[a-z]%',@)-1,'')+'.' -- remove lead up to first A-Z char *
    set @j=patindex('%[^a-z]%',@) -- find first non A-Z char. The +'.' above makes sure there is one
    if @j>2insert[ ] select lower(left(@,@j-1)) -- insert only words >1 char
    set @=stuff(@,1,@j,'') -- remove word and trailing non A-Z char
end;

select top(22)s,count(*)c
into #
from[ ]
where ',the,and,of,to,it,in,or,is,' not like '%,'+s+',%' -- exclude list
group by s
order by 2desc; -- highest occurence, assume no ties at 22!

-- 80 - 2 vertical bars - 2 spaces = 76
-- @w = weighted frequency
-- this produces a line equal to the length of the max occurence (max(c))
select @w=min((76.-len(s))/c),@=' '+replicate('_',max(c)*@w)
from #;

-- for each word, append it as a new line. note: embedded newline
select @=@+'
|'+replicate('_',c*@w)+'| '+s+' 'from #;
-- note: 22 words in a table should always fit on an 8k page
--       the order of processing should always be the same as the insert-orderby
--       thereby producing the correct output

print @ -- output

Python, 250 chars

borrowing from all the other Python snippets

import re,sys
t=re.findall("\w+","".join(sys.stdin).lower())
W=sorted((-t.count(w),w)for w in set(t)-set("the and of to a i it in or is".split()))[:22]
Z,U=W[0],lambda n:"_"*int(n*(76.-len(Z[1]))/Z[0])
print"",U(Z[0])
for(n,w)in W:print"|"+U(n)+"|",w

If you're cheeky and put the words to avoid as arguments, 223 chars

import re,sys
t=re.findall("\w+","".join(sys.stdin).lower())
W=sorted((-t.count(w),w)for w in set(t)-set(sys.argv[1:]))[:22]
Z,U=W[0],lambda n:"_"*int(n*(76.-len(Z[1]))/Z[0])
print"",U(Z[0])
for(n,w)in W:print"|"+U(n)+"|",w

Output is:

$ python alice4.py  the and of to a i it in or is < 11.txt 
 _________________________________________________________________________
|_________________________________________________________________________| she
|_______________________________________________________________| you
|____________________________________________________________| said
|_____________________________________________________| alice
|_______________________________________________| was
|___________________________________________| that
|____________________________________| as
|________________________________| her
|_____________________________| at
|_____________________________| with
|____________________________| s
|____________________________| t
|__________________________| on
|__________________________| all
|_______________________| this
|_______________________| for
|_______________________| had
|_______________________| but
|______________________| be
|_____________________| not
|____________________| they
|____________________| so

Groovy, 250

Code:

m=[:]
(new URL(args[0]).text.toLowerCase()=~/\w+/).each{it==~/(the|and|of|to|a|i[tns]?|or)/?:(m[it]=1+(m[it]?:0))}
k=m.keySet().sort{a,b->m[b]<=>m[a]}
b={d,c,b->println d+'_'*c+d+' '+b}
b' ',z=77-k[0].size(),''
k[0..21].each{b'|',m[it]*z/m[k[0]],it}

Execution:

$ groovy wordcount.groovy http://www.gutenberg.org/files/11/11.txt

Output:

 __________________________________________________________________________  
|__________________________________________________________________________| she
|________________________________________________________________| you
|_____________________________________________________________| said
|_____________________________________________________| alice
|_______________________________________________| was
|____________________________________________| that
|____________________________________| as
|_________________________________| her
|______________________________| at
|______________________________| with
|_____________________________| s
|_____________________________| t
|___________________________| on
|__________________________| all
|________________________| this
|_______________________| for
|_______________________| had
|_______________________| but
|______________________| be
|______________________| not
|____________________| they
|____________________| so

N.B. this follows relaxed rules re: long strings

Q,194

{t::y;{(-1')t#(.:)[b],'(!:)[b:"|",/:(((_)70*x%(*:)x)#\:"_"),\:"|"];}desc(#:')(=)($)(`$inter\:[(,/)" "vs'" "sv/:"'"vs'a(&)0<(#:')a:(_:')read0 -1!x;52#.Q.an])except`the`and`of`to`a`i`it`in`or`is`}

the function takes two arguments: one a file containing the text and the other is the number of lines of the chart to display

q){t::y;{(-1')t#(.:)[b],'(!:)[b:"|",/:(((_)70*x%(*:)x)#\:"_"),\:"|"];}desc(#:')(=)($)(`$inter\:[(,/)" "vs'" "sv/:"'"vs'a(&)0<(#:')a:(_:')read0 -1!x;52#.Q.an])except`the`and`of`to`a`i`it`in`or`is`}[`a.txt;20]

output

|______________________________________________________________________|she
|____________________________________________________________|you
|__________________________________________________________|said
|___________________________________________________|alice
|_____________________________________________|was
|_________________________________________|that
|__________________________________|as
|_______________________________|her
|_____________________________|with
|____________________________|at
|___________________________|t
|___________________________|s
|_________________________|on
|_________________________|all
|_______________________|this
|______________________|for
|______________________|had
|_____________________|but
|_____________________|be
|_____________________|not