Export of positions for each sequence at a particular column

Requested by Hari Jayaram via Jalview-Discuss:
http://www.jalview.org/pipermail/jalview-discuss/2014-September/001050.html
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Hi All,
I was wondering if there is a way to get all the residue positions for a particular selected column in an alignment
for eg.
I have 83 sequences in an alignment, I select a particular column , by clikcing on top ,and get the red bar. After this I can mouse over each sequence and see the residue numbers in the bottom.
Is there a way to bulk - output all the residue numbers at a particular column position?
So the output would look like
gi 12134567 833, P
gi 23456789 782 P
gi 12456789 830 P
gi 32737237 - -
....and so on for all 83 sequences more sequences

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