7

I'd like to know if there is a more efficient/pythonic way to add multiple numpy arrays (2D) rather than:

def sum_multiple_arrays(list_of_arrays):
   a = np.zeros(shape=list_of_arrays[0].shape) #initialize array of 0s
   for array in list_of_arrays:
      a += array
   return a

Ps: I am aware of np.add() but it works only with 2 arrays.

heresthebuzz
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3 Answers3

11
np.sum(list_of_arrays, axis=0)

should work. Or

np.add.reduce(list_of_arrays).
hpaulj
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2

The simplest most Pythonic solution is simply to use sum(), like so:

sum(list_of_arrays)
Moot
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0

i know the question says numpy, but here's a pure python answer in case someone needs it.

map(sum, zip(a,b)) which returns a generator. you can also do list(map(sum, zip(a,b))) to get a list

Nande
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