numpy.sin(pi) returns negative value

Question

The following code:

a = numpy.sin(2. * numpy.pi)
print(a < 0)

return \"True\". But in reality a = 0. How could I fix that? In addition,

Answer 1

>>> import numpy
>>> a = numpy.sin(2. * numpy.pi)
>>> numpy.allclose(a, 0)
True
>>> numpy.clip(numpy.array([-0.1, 1.0, 2.0]), 0, np.inf)
array([ 0.,  1.,  2.])