myArray = [1, 2, 3] len(myArray) #output 3
from collections import Counter values=np.ones(10) Counter(values)
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}