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Date: Sat, 12 Nov 2016 10:16:46 -0800 (PST)
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Subject: matrix manipulation
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Xref: news.eternal-september.org comp.lang.ada:32291
Date: 2016-11-12T10:16:46-08:00
List-Id: <comp.lang.ada>

What is an elegant way to program exchange of columns in a matrix. 
Application: 
C is a matrix. Cj be the j-th column of C.
Sort C1,C2, ..., Cn in non increasing order with respect to their first component.
I tried and ended up in a very messy program, as I had to sort the first components first, remember their new index and then reconstruct the matrix.