## 常规创建方法
a = np.array([2,3,4])
b = np.array([2.0,3.0,4.0])
c = np.array([[1.0,2.0],[3.0,4.0]])
d = np.array([[1,2],[3,4]],dtype=complex) # 指定数据类型
print a, a.dtype
print b, b.dtype
print c, c.dtype
print d, d.dtype
[2 3 4] int32
[ 2. 3. 4.] float64
[[ 1. 2.]
[ 3. 4.]] float64
[[ 1.+0.j 2.+0.j]
[ 3.+0.j 4.+0.j]] complex128
https://blog.csdn.net/sinat_34474705/article/details/74458605
