Well, the general algorithm might look like this:

First, open your file using open().

Then, in cycle, you read your file line by line, split it using split() or s///, find values of your interest, do calculations and form a content for new file in an array of lines. After cycle is done, just close this file, maybe rename it for backup version, then open it for write and push there your array with newly formed lines.

In reply to Re: average a column in tab-delimited file by fisher
in thread average a column in tab-delimited file by garyboyd

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