1.创建单位阵
d = np.eye(2) # Create a 2x2 identity matrix print d # Prints "[[ 1. 0.] # [ 0. 1.]]"2.创建随机阵
e = np.random.random((2,2)) # Create an array filled with random values print e # Might print "[[ 0.91940167 0.08143941] # [ 0.68744134 0.87236687]]"3.3整型和切片同时访问数组时，访问结果会降阶
a = np.array([[1,2,3,4], [5,6,7,8], [9,10,11,12]]) row_r1 = a[1, :] # Rank 1 view of the second row of a row_r2 = a[1:2, :] # Rank 2 view of the second row of a print row_r1, row_r1.shape # Prints "[5 6 7 8] (4,)" print row_r2, row_r2.shape # Prints "[[5 6 7 8]] (1, 4)" col_r1 = a[:, 1] col_r2 = a[:, 1:2] print col_r1, col_r1.shape # Prints "[ 2 6 10] (3,)" print col_r2, col_r2.shape # Prints "[[ 2] # [ 6] # [10]] (3, 1)"python-numpy-tutorial汉语版
numpy tutorial 详细教程汉语版
这个知乎帖子上都是干货
