Comparison between keys in hash

sarvan has asked for the wisdom of the Perl Monks concerning the following question:

Hi everyone,

The below is my script.

#! /usr/bin/perl

$str1='It is a guide to action which ensures that the military always 
+obey the commands of the party.'; chomp($str1);

$str2='It is a guide to action that ensures that the military will for
+ever heed Party commands is a guide.'; chomp($str2);



@arr1=split(/\s+/, $str1);

$n=0;

%result=();
%output=();
for($i=0; $i<$#arr1;$i++) {
  $t1="$arr1[$i] $arr1[$i+1] $arr1[$i+2]";

        @pattern_word_count=split(/\s/, $t1);

        $space_count=@pattern_word_count;

        if($space_count == 3) {

                if($str2=~/$t1/) {

                        $occurence=`echo $str2 | grep -o '$t1' |wc -l`
+; chomp($occurence);

                        $result{$occurence}=$t1;
      print $i+1,"\t\t",$occurence,"\t\t\t$t1\n";

                        $n++;

               }
                if($str1=~/$t1/) {

                        $occurence1=`echo $str1 | grep -o '$t1' |wc -l
+`; chomp($occurence1);

                       $output{$occurence1}=$t1;
                        print $i+1,"\t\t",$occurence1,"\t\t\t$t1\n";

               }
}
}
print "\n\nTotal Matches : $n\n";
[download]

In this code, i am just comparing $t1 with $str1,$str2 and counting the no.of times it appears.. Then, i store the no.of occurence in two seperate hashes..(%result,%output)

My question now is, i want to compare the keys of first hash with the keys of 2nd hash and find the which has minimum value. This comparison has to be done for all the keys in both hashes.. Any suggestions

Comment on Comparison between keys in hash Download Code

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Re: Comparison between keys in hash by jethro (Monsignor) on Jul 06, 2011 at 14:27 UTC
Are you really counting words with a shell command? Check this out: `my $string="It is a guide to action which ensures that the military al +ways obey the commands of the party"; my %counts; foreach (split(' ',$string)) { $counts{$_}++; } foreach (keys %counts) { print "Word '$_' occurs $counts{$_} times\n"; }` [download] will print `Word 'the' occurs 3 times Word 'It' occurs 1 times Word 'a' occurs 1 times Word 'of' occurs 1 times Word 'ensures' occurs 1 times Word 'which' occurs 1 times Word 'commands' occurs 1 times Word 'that' occurs 1 times Word 'is' occurs 1 times Word 'to' occurs 1 times Word 'always' occurs 1 times Word 'military' occurs 1 times Word 'guide' occurs 1 times Word 'party' occurs 1 times Word 'action' occurs 1 times Word 'obey' occurs 1 times` [download] Oh, and the problem you were asking about: Just use foreach (key ...) on one hash and compare with the second hash. Then do the same with the second hash but only look at keys not in the first hash (as they are the only ones not handled by the first foreach loop).	[reply] [d/l] [select]
Re: Comparison between keys in hash by i5513 (Pilgrim) on Jul 06, 2011 at 14:49 UTC
Really you should switch to use strict and use warnings Here is your code rewritten in 'pure perl', with this notes: - my @xx= $str =~ /(xxx)/g # return array with matches - scalar @xx # how many items are in @xx - you should add use strict your self to the script - it is not needed to go to #arr in the loop - I really doesn't understand what you want to say in the last paragraph, so my code is only a guess See perlretut for more info in first note #! /usr/bin/perl $str1='It is a guide to action which ensures that the military always +obey the commands of the party.'; chomp($str1); $str2='It is a guide to action that ensures that the military will for +ever heed Party commands is a guide.'; chomp($str2); @arr1=split(/\s+/, $str1); $n=0; %result=(); %output=(); for($i=0; $i<$#arr1-1;$i++) { $t1="$arr1[$i] $arr1[$i+1] $arr1[$i+2]"; if(@matchs=$str2=~/($t1)/g) { $result{@matchs}=$t1; print $i+1,"\t\t",scalar @matchs,"\t\t\t$t1\n"; $n++; } if(@matchs=$str1=~/($t1)/g) { $output{@matchs}=$t1; print $i+1,"\t\t",scalar @matchs,"\t\t\t$t1\n"; } } print "\n\nTotal Matches : $n\n"; if ((sort keys %output)[0] > (sort keys %result)[0]) { print "result has the minor value\n"; } elsif ((sort keys %output)[0] < (sort keys %result)[0]) { print "output has the minor value\n"; } else { print "Both has the same minor value\n"; } [download] PD to perlmonks admins: I really hate to have add <br> in every line :( when I'm commenting or posting	[reply] [d/l]
Re^2: Comparison between keys in hash by MidLifeXis (Monsignor) on Jul 06, 2011 at 15:09 UTC
PD to perlmonks admins: I really hate to have add `<br>` in every line :( when I'm commenting or posting Posts on PerlMonks are html formatted. Your list could have been formatted as an html list using `<ul><li>..</li>..</ul>`, and your paragraphs could have been formatted as `<p>..</p>` blocks. (Update) See the following links for more information: Markup in the Monastery Perl Monks Approved HTML tags What shortcuts can I use for linking to other information? Writeup Formatting Tips --MidLifeXis	[reply] [d/l] [select]
Re^3: Comparison between keys in hash by i5513 (Pilgrim) on Jul 06, 2011 at 16:48 UTC
For both, (MidLifeXis and zek152): I was talked before (other monk said me) about like html format when posting here, and I read those tips. And I accept, I will tag my post with html tags ... But would be wonderful to have an option in your perlmonks settings page where return carriage + newline where respected How <br> is short than <p> </p>, I will try to use the first Thank you both!	[reply]
Re^2: Comparison between keys in hash by zek152 (Pilgrim) on Jul 06, 2011 at 15:12 UTC
i5513. You don't have to use <br>. If you use <p> .... </p> the text will be automatically wrapped.	[reply]
Re^2: Comparison between keys in hash by sarvan (Sexton) on Jul 06, 2011 at 15:06 UTC
Hi i5513, What i meant in the last statement is. I want to compare the keys at two hashes. let me be specific. The whole program splits a sentence and compares each words of the sentence with two sentence i.e($str1,$str2). What i needed is: for eg. if "the" word occurs in $str1 two times and $str2 one time. i want find the minimum value i.e is 1. Same procedure for all the words in the sentence. The end output should give me the Word string and Its minimum count(after comparing counts in $str1 & $str2)..	[reply]
Re^3: Comparison between keys in hash by i5513 (Pilgrim) on Jul 06, 2011 at 16:40 UTC
Then I would change your hash to: `$counting{word}{$word}{str1}=$counter; $counting{word}{$word}{str2}=$counter;` [download] And then (see here for min function examples): `foreach my $word (keys %{$counting{word}}) { print "$word\t", min ($counting{word}{$word}{str1}, $counting{word}{$word}{str2}) }` [download]	[reply] [d/l] [select]
Re^4: Comparison between keys in hash by sarvan (Sexton) on Jul 07, 2011 at 06:14 UTC
Re^5: Comparison between keys in hash by i5513 (Pilgrim) on Jul 07, 2011 at 08:11 UTC
Some notes below your chosen depth have not been shown here
Re^3: Comparison between keys in hash by jdporter (Paladin) on Jul 06, 2011 at 15:09 UTC
Sounds like homework.	[reply]
Re^3: Comparison between keys in hash by Anonymous Monk on Jul 06, 2011 at 15:16 UTC
let me be specific. You're just repeating yourself again, or, your homework assignment Is PerlMonks a good place to get answers for homework?	[reply]
Re: Comparison between keys in hash by Anonymous Monk on Jul 06, 2011 at 14:12 UTC
Any suggestions Don't abandon strict and warnings, you need them if you want to cut your development time in half! Don't shell out (backticks) or if shelling out, do use taint mode (-T) Do use quotemeta when constructing a regex, or you could even use Regexp::English - Perl module to create regular expressions more verbosely Do incorporate the answers (code) you asked for and got, and don't switch to shell/grep Read perlintro keys, each, http://perldoc.perl.org/perlop.html#Relational-Operators Read Tutorials Data Type: Hash	[reply]