[SciPy-user] manipulate arrays/matrices

[David Douard]

On Wed, Jun 07, 2006 at 09:42:19AM +0200, Nils Wagner wrote:
> Hi all,
> 
> Is there a better way to interchange two rows/columns of an array ?
> 


Hi, using numpy:

from numpy import *

A = diag(arange(1,n+1))+diag(ones(n-2),2)+diag(ones(n-2),-2)

# swap rows 1 and 3
A[array([1,3])] = A[array([3,1])]

#swap columns 1 and 3
A[:,array([1,3])] =  A[:,array([3,1])]




David

-- 
David Douard                             LOGILAB, Paris (France)
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