Question

matlab 中angle的用法

matlab中angle的具体用法，举个例子说明也行，谢谢。。

Answer 1

matlab中angle用来求复数矩阵相位角的弧度值，其取值为-pi到pi。

示例：

Z = [ 1 - 1i   2 + 1i   3 - 1i   4 + 1i
      1 + 2i   2 - 2i   3 + 2i   4 - 2i
      1 - 3i   2 + 3i   3 - 3i   4 + 3i
      1 + 4i   2 - 4i   3 + 4i   4 - 4i ]
      
P = angle(Z)

得到的结果为：

P =
   -0.7854    0.4636   -0.3218    0.2450
    1.1071   -0.7854    0.5880   -0.4636
   -1.2490    0.9828   -0.7854    0.6435
    1.3258   -1.1071    0.9273   -0.7854

angle采用的算法：angle(z) = imag(log(z)) = atan2(imag(z), real(z)).

详情可参考help angle

Answer 2

P = angle(Z) returns the phase angles, in radians, for each element of complex array Z. The angles lie between . For complex Z, the magnitude R and phase angle theta are given by R = abs(Z)
theta = angle(Z)
and the statement Z = R.*exp(i*theta)
converts back to the original complex Z.