Calculate the Jaccard Similarity Coefficient. NAME Set::Jaccard::SimilarityCoefficient - Calculate the Jaccard Similarity Coefficient of 2 sets VERSION # VERSION SYNOPSIS \$res = Set::Jaccard::SimilarityCoefficient::calc(\@set_a, \@set_b); OR my \$a = Set::Scalar->new(@set_a); my \$b = Set::Scalar->new(@set_b); \$res = Set::Jaccard::SimilarityCoefficient::calc(\$a, \$b); DESCRIPTION Set::Jaccard::SimilarityCoefficient lets you calculate the Jaccard Similarity Coefficient for either arrayrefs or Set::Scalar objects. Briefly, the Jaccard Similarity Coefficient is a simple measure of how similar 2 sets are. The calculation is (in pseudo-code): count(difference(SET-A, SET-B)) / count(union(SET-A, SET-B)) There is a Jaccard Similarity Coefficient routine already in CPAN, but it is specialized for use by Text::NSP. I wanted a generic routine that could be used by anyone so Set::Jaccard::SimilarityCoefficient was born. SUBROUTINES/METHODS calc(A, B) calculates the Jaccard Similarity Coefficient for the arguments A and B. A and B can be either array references or Set::Scalar objects. DIAGNOSTICS new() will complain if A or B is empty, not either a reference to an array, or not a Set::Scalar object. calc() could theoretically throw DivideByZeroException when the union of the two sets has 0 members. However, that would require set A or set B to have 0 members, which was previously prohibited by the prohibition on empty sets. CONFIGURATION AND ENVIRONMENT This module should work wherever Perl works. DEPENDENCIES Set::Scalar INCOMPATIBILITIES None that I know of. BUGS AND LIMITATIONS There are no bugs that I know of. Given that this is non-trivial code, there will be bugs. The types of arguments are limited to either array references or Set::Scalar objects. AUTHOR Mark Leighton Fisher, LICENSE AND COPYRIGHT Set::JaccardSimilarityCoefficient is licensed under the same terms as Perl itself. POD ERRORS Hey! The above document had some coding errors, which are explained below: Around line 26: Unknown directive: =function