What exactly are you having problems with?  Reading/processing lines in pairs, determining if there is a match, averaging the length values, writing out the resulting lines, or something else?

The monks are usually more inclined to help if you show some initial effort, i.e. the code you've tried so far.

In reply to Re: Combining matching lines in a TAB seperated textfile by Eliya
in thread Combining matching lines in a TAB seperated textfile by Wobbel

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