python - Sum ndarray values -


is there easier way sum of values (assuming numbers) in ndarray :

import numpy np  m = np.array([[1,2],[3,4]])  result = 0 (dim0,dim1) = m.shape in range(dim0):     j in range(dim1):         result += m[i,j]  print result

the above code seems verbose straightforward mathematical operation.

thanks!

just use numpy.sum():

result = np.sum(matrix)

or equivalently, .sum() method of array:

result = matrix.sum()

by default sums on elements in array - if want sum on particular axis, should pass axis argument well, e.g. matrix.sum(0) sum on first axis.

as side note "matrix" numpy.ndarray, not numpy.matrix - they different classes behave differently, it's best avoid confusing two.


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