Comparison of np.dot and operator *

np.dot calculate the dot product of two arrays. For 2-D arrays, the matrix multiplication result is returned.

 The * operator calculate the element-wise multiplication. It will expand its dimension (called broadcasting) if the dimension does not match.

The best way to explain this is through some actual code

	import numpy as np
	# Example 1
	vec1 = np.array([1, 2])
	vec2 = np.array([2, 3])
	vec1*vec2
	# Return
	# array([2, 6])
	np.dot(vec1, vec2)
	# Return
	# 8
	# Example 2
	vec3 = np.array([[1, 2], [3, 4]])
	vec4 = np.array([1, 2])
	vec3*vec4
	# Return
	# array([[1, 4], [3, 8]])
	np.dot(vec3, vec4)
	# Return
	# array([5, 11])
	# Example 3
	vec5 = np.array([[1, 2, 3], [4, 5, 6]])
	vec6 = np.array([1, 2])
	vec5.T*vec6
	# Return
	# array([[1, 8], [2, 10], [3, 12]])
	np.dot(vec5.T, vec6)
	# Return
	# array([9, 12, 15])

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