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.
来源:https://stackoverflow.com/questions/42517281/difference-between-numpy-dot-and-a-dotb