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matrix vector
From: 
John W. Eaton 
Subject: 
matrix vector 
Date: 
Mon, 23 Jun 2003 12:55:34 0500 
On 23Jun2003, Matthew Wollenweber <address@hidden> wrote:
 i'm not too familiar with fortran.

 I'm curious if I have:

 Matrix M(x,y);
 double *P;

 P = M.fortran_vec();

 Is P in raster order? If anyone Is particularly use to image processing,
 I'm attempting to use octave with Thevenaz and Unser's spline code and i'm
 not sure if I'm passing in the Matrix correctly.
I'm not sure what "raster order" means.
The data in an Octave Matrix object is stored in columnmajor order.
I.e., for the matrix
[1,2;
3,4]
the vector of values returned by fortran_vec() will be
[1, 3, 2, 4]
You could have verified this by either looking at the code for the
Matrix/Array classes in Octave, or by doing a simple experiment.
jwe

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 matrix vector, Matthew Wollenweber, 2003/06/23
 matrix vector,
John W. Eaton <=