You've "been trying for a long time now", so what did you try and what didn't work? This community is happy to help debug, but we are not a code-writing service.

I would in particular point out Text::CSV for parsing the file and Relational Operators and Foreach Loops for processing.

In reply to Re: for each unique value in a column find the max value..need perl script by kennethk
in thread for each unique value in a column find the max value..need perl script by qmenon

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