Re: Re-ordering columns or rows of an array efficiently

On 29 nov, 05:17, Mike <mkjoh...@xxxxxxxxx> wrote:
Many thanks to all for the replies and suggestions. I will try each of
the suggestions to see which is most efficient for my application. In
this case, there are more than 10,000 rows and columns in a square
array. The re-ordering is unique. Again, thanks to everyone for making
my process of moving from MATLAB to FORTRAN as simple as possible. :)

Best regards,

Mike

A last solution : you could also never reorder the array just keeping
in parallel the initial array and the permutation vector (and possibly
the reverse permutation vector too). This is often what I do with
large matrices initialized under a fixed form but inversed taking into
account a permutation ...
.

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