I have my array, say: [10, 6, 4, 12].
I am interested in finding a vector of cumulative sums, i.e.:
[10, 16, 20, 32].
Obvious approach would be to use a for loop:
r = []
for ind in range(4):
r.append(s[ind]) # s is [10, 6, 4, 12]
r = cumsum(r)
However, this seems really inefficient. I want to ask if there is a pre-defined function or I should specify specific arguments in cumsum.
there are many ways like np.cumsum or python 3.2+ you can use itertools.accumulate
By Itertool:
l = [10, 6, 4, 12]
from itertools import accumulate
print(list(accumulate(l)))
output:
[10, 16, 20, 32]
Using numpy:
import numpy as np
print(np.cumsum(l))
output:
[10, 16, 20, 32]