例题2.25
例题2.25代码
import numpy as np
a1 = np.array([1,2,3,4])
a2 = a1.astype(float)
a3 = np.array([1,2,3,4], dtype = float)
print(a1.dtype); print(a2.dtype); print(a3.dtype)
b = np.array([[1,2,3], [4,5,6]])
c = np.arange(1, 5)
d = np.linspace(1, 4, 4)
e = np.logspace(1, 3, 3, base = 2)
