OK ... here's a small code example to get you started. (You'll still want to hit CPAN for a PDF parsing module, though.)

#!/usr/bin/perl -w
use strict;
use warnings;

# Tell perl to split records on periods.
$/ = '.';

my %words;

# Read successive lines from our __DATA__section
while (<DATA>) {

        # Skip the sentence unless it contains the text "asia"
        next unless m/asia/i;

        # Remove extraneous characters
        tr/a-zA-Z/ /cs;

        # Show each sentence we keep
        print "<$_>\n";

        # Increment the counter for each word found
        map { $words{$_}++ } split;
}

print   "\n\n"
.       "Count  Word\n"
.       "-----  -------------\n";

# Print all words in the sentences that appear more than once.
for (sort keys %words) {
        next unless $words{$_} > 1;
        print "$words{$_}\t$_\n";
}


__DATA__
Now is the time for all good.  Men to come to the Asia of
their party.  The quick red fox jumped over the calico cat.
One fish two fish asiatic fish blue fish.  Zoom.
When must we come to asia to see the fox?  Dolum ipsum dolor est.
Canem homo mordet.  I would guess that few people speak latin in Asia.
Perhaps many more asians speak greek.  But how would I know?

[download]
When run on my machine, it gives us:

roboticus~
$ ./re_test.pl
< Men to come to the Asia of their party >
< One fish two fish asiatic fish blue fish >
< When must we come to asia to see the fox Dolum ipsum dolor est >
< I would guess that few people speak latin in Asia >
< Perhaps many more asians speak greek >


Count   Word
-----   -------------
2       Asia
2       come
4       fish
2       speak
2       the
4       to

roboticus~
$

[download]
...roboticus

In reply to Re^3: Word Frequency in Particular Sentences by roboticus
in thread Word Frequency in Particular Sentences by Anonymous Monk

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