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matrix vector
From: |
John W. Eaton |
Subject: |
matrix vector |
Date: |
Mon, 23 Jun 2003 12:55:34 -0500 |
On 23-Jun-2003, 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 column-major 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 <=