TensorFlow之Numpy(3)
官网:www.numpy.org
基本内容有:
代码示例:
1 import numpy as np 2 3 #数组定义 4 vector = np.array([1, 2, 3]) 5 6 #长度 7 vector.shape 8 #大小 9 vector.size 10 #维度/阶数 11 vector.ndim 12 #类型 13 type(vector) 14 15 matrix = np.array([ [1, 2], [3, 4] ]) 16 matrix.shape 17 matrix.ndim 18 matrix.size 19 type(matrix)
矩阵转置:
1 one = np.arange(12) 2 3 #输出:array([ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]) 4 5 #改变形状 6 one.reshape((3,4)) 7 8 #输出: 9 #array([ [0, 1, 2, 3], 10 # [4, 5, 6, 7], 11 # [8, 9, 10, 11]]) 12 13 two = one.reshape((3,4)) 14 15 two.ndim 16 17 two.shape 18 19 two.size
numpy中,全0、1和单位矩阵:
1 import numpy as np 2 3 #全0矩阵(m行n列) 4 np.zeros((m, n)) 5 6 #全1矩阵(m行n列) 7 np.ones((m, n)) 8 9 #单位矩阵 10 np.eye(n)