ComplexField.power gives invalid return values for negative integer reals with a real power

[lokedhs]

Example:

ComplexField.power(Complex(-3.0, 0.0), 0.5)

This results in a complex result where both the real and imaginary parts are NaN.

Workaround:

ComplexField(Complex(-3.0, 0.0), Complex(0.5, 0.0))

[SPC-code]

Thank you, I've reproduced it on the latest build.

[SPC-code]

Thanks again, the problem was in optimization made for complex numbers without real part: https://github.com/SciProgCentre/kmath/commit/8a754ace199d84959978b78fb1b175595a1d7af3.