in reply to Inserting a header into outfile
Please read How do I post a question effectively?. Please be sure when you post that the code runs, and provide expected output from provided inputs, all wrapped in <code> tags. In this scenario, that dangling use ; at the top of the file is a syntax error and is a red flag that you didn't test what you posted.
What are you using as learning material? Try Learn Perl in 2 hours 30 minutes or http://learn.perl.org. I note that you do not use strict or warnings. It's understandable that an old script might not have these, but any new code should use them. See Use strict warnings and diagnostics or die.
The easiest solution for your spec would be to insert
before that last foreach loop. Is there subtlety in the challenge I am missing?print "ETXLinkID,TranscomLinkID,TranscomLen,TranscomLenFrac,EtxLenFrac +,EtxLen\n";
#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.
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