Rational powers with negative base
Issue #984
new
I tried to calculate (-20)^(1/7) but the calculation yields NaN as if it was not defined. With any other odd n (except those being 7 or 49), the computation of (-20)^(1/n) is successful. This same issue occurs with any negative base for powers 1/7 and 1/49, but no other power of form 1/n with an odd n.
Is this somehow due to the algorithm that the power function ^ or what might cause this unexpected behavior?
Comments (2)
-
repo owner -
Raising a negative number to a fractional number is poorly defined. A real solution exists if a) the exponent is rational and b) the reduced denominator is odd.
I have implemented this in
hmath.cpp:1251
. That's the code that needs to be debugged. - Log in to comment
@Tey' @Pol Welter @Hadrien Theveneau Anyone aware of this? Thoughts?