import numpy as np
data1 =np.array([1,2,3,4,5])
print(data1)
data2=np.array([[1,2],
[3,4]])
print(data2)
#打印矩阵维度
print(data1.shape,data2.shape)
#zero ones
print(np.zeros([2,3]))
print(np.ones([2,2]))
矩阵的增删改查
import numpy as np
data1=np.ones([2,2])
print(data1)
data1[0,1]=2
print(data1)
print(data1[0,1])
输出:
[[1. 1.]
[1. 1.]]
[[1. 2.]
[1. 1.]]
2.0
print(data1*3)
print(data1/3)
print(data1+3)
print(data1-3)
[[3. 6.]
[3. 3.]]
[[0.33333333 0.66666667]
[0.33333333 0.33333333]]
[[4. 5.]
[4. 4.]]
[[-2. -1.]
[-2. -2.]]
#根据结果可以得知前面的运算并没有改变data1的值