import timeit
print(timeit.timeit('numpy.isnan(x)', setup=r'''
import numpy
x = numpy.random.choice([0.5, numpy.nan], size=10000)''', number=1000))
print(timeit.timeit('[math.isnan(num) for num in x]', setup=r'''
import math
import random
x = random.choices([0.5, float('nan')], k=10000)''', number=1000))
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