On Thu, Sep 3, 2009 at 00:09, Sturla Molden
Chad Netzer skrev:
I'd also like to, if possible, have a specialized 2D version, since image media filtering is one of my interests, and the C version works on 1D (raveled) arrays only. I agree. NumPy (or SciPy) could have a select module similar to the sort module. If the select function takes an axis argument similar to the sort functions, only a small change to the current np.median would needed.
Take a look at this:
http://projects.scipy.org/numpy/attachment/ticket/1213/_selectmodule.pyx
Here is a select function that takes an axis argument. There are specialized versions for 1D, 2D, and 3D. Input can be contiguous or not. For 4D and above, axes are found by recursion on the shape array. Thus it should be fast regardless of dimensions.
When he is talking about 2D, I believe he is referring to median filtering rather than computing the median along an axis. I.e., replacing each pixel with the median of a specified neighborhood around the pixel. -- Robert Kern "I have come to believe that the whole world is an enigma, a harmless enigma that is made terrible by our own mad attempt to interpret it as though it had an underlying truth." -- Umberto Eco