for f(x,y) you can use f(x,y)->(a,b) 2D LUT (Look Up Table) But the stored grid points must be selected so dense so that there is max one bump per grid rectangle, otherwise interpolation would not work correctly. If you want to use linear interpolation then the local min/max must be points inside LUT, for polynomial … Read more
You can just use image to index into lut if lut is 1D. Here’s a starter on indexing in NumPy: http://www.scipy.org/Tentative_NumPy_Tutorial#head-864862d3f2bb4c32f04260fac61eb4ef34788c4c In [54]: lut = np.arange(10) * 10 In [55]: img = np.random.randint(0,9,size=(3,3)) In [56]: lut Out[56]: array([ 0, 10, 20, 30, 40, 50, 60, 70, 80, 90]) In [57]: img Out[57]: array([[2, 2, 4], … Read more
You are looking for a Lookup with multiple criteria. A quick search gives several useful links, listed below. I have marked with * those that I have answered. I have filtered out some of the links that actually deal with other issues. As seen in the links, there are several options to achieve your goal. … Read more