[numpy] nonzero

nonzero

array중 0 이 아닌 index를 얻고자할때 사용한다.

1차원

import numpy as np

a = np.array([0,1,2,3,4,5,0,1,2,3,4])

nonzeroList = a.nonzero()

print(nonzeroList)
#[1,2,3,4,5,7,8,9,10], dtype=int64

2차원

import numpy as np

b = np.array([0,1,2,3,0],[0,1,2,3,0])

print(b.nonzero())
# [0,0,0,1,1,1]
# [1,2,3,1,2,3]

print(np.transpose(b.nonzero()))
# merge