Iterating over Numpy matrix rows to apply a function each?

Question

I want to be able to iterate over the matrix to apply a function to each row. How can I do it for a Numpy matrix ?

Answer 1

You can use numpy.apply_along_axis(). Assuming that your array is 2D, you can use it like:

import numpy as np mymatrix = np.matrix([[11,12,13],                       [21,22,23],                       [31,32,33]]) def myfunction(x):     return sum(x)  print(np.apply_along_axis(myfunction, axis=1, arr=mymatrix)) #[36 66 96]