import numpy as np
x = np.empty([3,2], dtype = int)
print (x)
import numpy as np # 默认为浮点数
x = np.zeros(5)
print(x) # 设置类型为整数
y = np.zeros((5,), dtype = np.int)
print(y) # 自定义类型
z = np.zeros((2,2), dtype = [('x', 'i4'), ('y', 'i4')])
print(z)
import numpy as np # 默认为浮点数
x = np.ones(5)
print(x) # 自定义类型
x = np.ones([2,2], dtype = int)
print(x)