On Mon, May 21, 2012 at 6:50 AM, Robert Jördens <jordens@gmail.com> wrote:

Hello,
I submitted two functions to numpy that sum 2d matrices along angled
cartesian or polar coordinates.
https://github.com/numpy/numpy/pull/230
The two functions certainly have their main application in image
processing and might be better suited for scipy of scikits-image.

sum_angle() is not much more than the old scipy.misc.pilutils.radon()
transform. But the later is deprecated and has several problems
(floats, non-conserved sum(), interpolation, speed) as discussed in
the pull request.

The new scikits-image.transform.radon() appears to be more generic but
a bit complicated and potentially even slower than the
imrotate()-based version in scipy.

Could you time the scikits-image version, it's not obvious from reading the code that it will be very slow?

Could sum_angle() and sum_polar() find a place in scipy or
scikits-image or are they simple enough to be useful for numpy?

My impression is that it would fit best in scikits-image. Perhaps ndimage would be a reasonable place too. It's too specialized for numpy imho.

Ralf