Python:numpy中shape和reshape的用法 | Reshape
>>>w=np.zeros((5,6))>>>warray([[0., 0., 0., 0., 0., 0.], [0., 0., 0., 0., 0., 0.], [0., 0., 0., 0., 0., 0.], [0., 0., 0., 0., 0., 0.], [0., 0., 0., 0., 0., 0.]])>>>w.shape[0]5>>>w.shape[1]6w是一个5行6列的矩阵w.shape[0]返回的是w的行数w.shape[1]返回的是w的列数================reshape用法====================importnumpyasnpa=np.array([1,2,3,4])b=np.array((5,6,7,8))c=np.array([[1,2,3,4],[4,5,6,7],[7,8,9,1]])print("a:",a)print("b:",b)print("c:...
>>> w=np.zeros((5,6))>>> warray([[ 0., 0., 0., 0., 0., 0.], [ 0., 0., 0., 0., 0., 0.], [ 0., 0., 0., 0., 0., 0.], [ 0., 0., 0., 0., 0., 0.], [ 0., 0., 0., 0., 0., 0.]])
>>> w.shape[0]5
>>> w.shape[1]6
w是一个5行6列的矩阵
w.shape[0]返回的是w的行数
w.shape[1]返回的是w的列数
================reshape用法====================
import numpy as np a=np.array([1,2,3,4]) b=np.array((5,6,7,8)) c=np.array([[1,2,3,4],[4,5,6,7],[7,8,9,1]]) print("a: ",a) print("b: ",b) print("c: ",c) print(c.dtype) a_r=a.reshape((2,2)) print("a_r: ",a_r) b_r=b.reshape((2,2)) print("b_r: ",b_r) d=a.reshape((-1,1)) print("d: ",d) e=a.reshape((1,-1)) print("e: ",e)运行结果:
a: [1 2 3 4]b: [5 6 7 8]c: [[1 2 3 4] [4 5 6 7] [7 8 9 1]]int32a_r: [[1 2] [3 4]]b_r: [[5 6] [7 8]]d: [[1] [2] [3] [4]]e: [[1 2 3 4]]