[Numpy-discussion] Change default order to Fortran order

[Sturla Molden]

Juan Nunez-Iglesias <jni.soma at gmail.com> wrote:

> The short version is that you'll save yourself a lot of pain by starting to
> think of your images as (plane, row, column) instead of (x, y, z). 

There are several things to consider here.

1. The vertices in computer graphics (OpenGL) are (x,y,z).

2. OpenGL rotation matrices and projection matrice are stored in column
major order.

3. OpenGL frame buffers are indexed (x,y) in column major order with (0,0)
being lower left.

4. ITK and VTK depends on OpenGL and are thus using column major order.

5. Those who use Matlab or Fortran in addition to Python prefer column
major order.

6. BLAS and LAPACK use column major order.

7. The common notation in image prorcessing (as opposed to computer
graphics in geberal) is indexing (row, column), in row major order, with
(0,0) being upper left.

All in all, this is a strong case for prefering column major order and the
common mathematical notation (x,y,z). 

Also notice how the ususal notation in image pricessing differs from
OpenGL.


Sturla