- `Y = imag (Z)`

Return the imaginary part of `Z` as a real number.

See also: `real`, `conj`.

### References

- https://www.mathworks.com/help/matlab/ref/imag.html
- https://octave.sourceforge.io/octave/function/imag.html
- https://mathworld.wolfram.com/ComplexNumber.html
- https://mathworld.wolfram.com/ImaginaryNumber.html
- https://mathworld.wolfram.com/ImaginaryUnit.html
- https://en.wikipedia.org/wiki/Complex_number
- https://en.wikipedia.org/wiki/Imaginary_number
- https://en.wikipedia.org/wiki/Imaginary_unit