Calculating a sum in numpy array [duplicate]

Question

I want to know how to get a sum of values in a 3x3 NumPy array with a loop. For example:

[[1,2,3],[4,5,6],[7,8,9]]

The output should be [6,15,24].

Check this docs.scipy.org/doc/numpy/reference/generated/numpy.sum.html — Ankit Agarwal
– Ankit Agarwal, Commented Sep 17, 2018 at 9:28

U13-Forward · Accepted Answer · 2018-09-17 09:28:18Z

1

Try using np.array.sum with axis argument as one:

arr.sum(1)

Example:

>>> arr=np.array([[1,2,3],[4,5,6],[7,8,9]])
>>> arr.sum(1)
array([ 6, 15, 24])

Or if it is a list:

np.sum(array,1)

Example:

>>> arr=[[1,2,3],[4,5,6],[7,8,9]]
>>> np.sum(arr,1)
array([ 6, 15, 24])
>>>

answered Sep 17, 2018 at 9:28

U13-Forward

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