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How do I find the percentage of similarity between strings?

by Superman (Acolyte)
on Apr 25, 2002 at 17:01 UTC ( #162038=categorized question: print w/replies, xml ) Need Help??
Contributed by Superman on Apr 25, 2002 at 17:01 UTC
Q&A  > strings


Description:

I have 2 strings which should be identical: 
$PDBline;
$XMLline;

[download]
and I test for this normally: 
if ($PDBline eq $XMLline){etc...}

[download]
However in the event that they dont match I want to do a percentage comparison where I match each word in $PDBline against the words in $XMLline.

So say I want a 75 % similarity between the 2 strings... 

my $threshold = 0.75;

my $counter = 0;

foreach my $word ( split ' ', $PDBline ) {
  $counter++ if $XMLline =~ /$word/;
}

[download]
Does this seem right or is there an easier way to do this??

Answer: How do I find the percentage of similarity between strings?
contributed by I0

use String::Approx 'adistr';

Answer: How do I find the percentage of similarity between strings?
contributed by The Mad Hatter

String::Approx is good as someone else said. So is Text::Levenshtein. With the values you can get from both modules, you should be able to do some math to get a percentage.

You might also want to read Levenshtein distance: calculating similarity of strings.

Answer: How do I find the percentage of similarity between strings?
contributed by chicks

I'm personally quite fond of Algorithm::Diff. It's line-oriented and you asked for word-oriented, so it might not work for what you're trying to do precisely.

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