scipy.linalg.

cosm#

scipy.linalg.cosm(A)[source]#

计算矩阵余弦。

此例程使用 expm 计算矩阵指数。

参数:

A(N, N) array_like: 输入数组

返回值:

cosm(N, N) ndarray: A 的矩阵余弦

示例

>>> import numpy as np
>>> from scipy.linalg import expm, sinm, cosm

欧拉恒等式（exp(i*theta) = cos(theta) + i*sin(theta)）应用于矩阵

>>> a = np.array([[1.0, 2.0], [-1.0, 3.0]])
>>> expm(1j*a)
array([[ 0.42645930+1.89217551j, -2.13721484-0.97811252j],
       [ 1.06860742+0.48905626j, -1.71075555+0.91406299j]])
>>> cosm(a) + 1j*sinm(a)
array([[ 0.42645930+1.89217551j, -2.13721484-0.97811252j],
       [ 1.06860742+0.48905626j, -1.71075555+0.91406299j]])