Difference between numpy.dot and a.dot(b)

问题:

Is there a difference between

import numpy as np
np.dot(a,b)

and

a.dot(b)

internally? I wasn't able to find any documentation on the latter method.

回答1:

If a is an array, they're equivalent. The docs you couldn't find for the dot method are here, and they boil down to "see numpy.dot".

If type(a) is not numpy.ndarray, then numpy.dot will convert a to an array and use the array for the multiplication, while a.dot will do whatever a's type says it does, or raise an AttributeError if a doesn't have a dot method.