학습일 : 2020.01.23
import numpy as np
random 서브모듈
np.random.rand(2, 3)
array([[0.76735987, 0.5378132 , 0.51796261],
[0.58758048, 0.63109737, 0.9175088 ]])
np.random.randn(3, 4) # 음수
array([[-0.30440149, -0.03354128, -0.05125848, 2.26147692],
[-1.26406315, -0.82020222, -0.02332504, -0.57736223],
[ 0.16765093, 0.32052709, 1.0308137 , -1.51300966]])