It really depends on the objective. You could count the occurrence of each word and compare frequencies. They could be identical but the text files could be completely different. A single 'not' could change the meaning of a text into its opposite. The 'diff' tool is useful to compare text files but mainly based on lines. You could consider your text file as a sequence of words and then apply a longest common subsequence algorithm as in Algorithm::Diff.

In reply to Re: Similarity measurement by hdb
in thread Similarity measurement by kennedy

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