[SciPy-User] permutation matrix in LU decomposition

Jason Grout jason-sage at creativetrax.com
Wed Nov 28 15:22:00 EST 2012


On 11/28/12 2:00 PM, Ralf Gommers wrote:
>
>
>
> On Mon, Nov 26, 2012 at 6:21 PM, Jason Grout
> <jason-sage at creativetrax.com <mailto:jason-sage at creativetrax.com>> wrote:
>
>     I just noticed that the permutation matrix P returned in scipy's LU
>     decomposition is the inverse (i.e., transpose) of the permutation matrix
>     returned from Matlab's LU function.  In scipy, A = PLU, but in Matlab,
>     PA=LU [1].  It's just a convention, of course, but perhaps a note about
>     this could be added to the relevant table row of
>     http://www.scipy.org/NumPy_for_Matlab_Users?
>
>
> Sure, done. Note that that page is a wiki, so feel free to make more
> updates.

Ah, right.  Had I realized that, I would have just made the update myself.

Thanks,

Jason




More information about the SciPy-User mailing list