count number of 1 in numpy array code example

Example 1: numpy count the number of 1s in array

a = numpy.array([0, 3, 0, 1, 0, 1, 2, 1, 0, 0, 0, 0, 1, 3, 4])
unique, counts = numpy.unique(a, return_counts=True)
dict(zip(unique, counts))
{0: 7, 1: 4, 2: 1, 3: 2, 4: 1}

Example 2: count values in array python

a = numpy.array([0, 3, 0, 1, 0, 1, 2, 1, 0, 0, 0, 0, 1, 3, 4])
unique, counts = numpy.unique(a, return_counts=True)
dict(zip(unique, counts))

# {0: 7, 1: 4, 2: 1, 3: 2, 4: 1}

Example 3: numpy count where

print(np.sum(a % 2 == 1))