Most likely explanation is that there's actually an empty line at the end of your data file, which in turn causes the last emelent of @SNPs to be an empty string, which in turn will cause the undefined $position

Depending on your editor, the empty line might not be easy to spot. Doing a hexdump or similar might help.

In reply to Re: Tracing an Uninitialized Error by Crackers2
in thread Tracing an Uninitialized Error by ccelt09

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