Optimizations for pow() with const non-integer exponent?

Question

I have hot spots in my code where I\'m doing pow() taking up around 10-20% of my execution time.

My input to pow(x,y) is very specific, so

Answer 1

Binomial series does account for a constant exponent, but you will be able to use it only if you can normalize all your input to the range [1,2). (Note that it computes (1+x)^a). You'll have to do some analysis to decide how many terms you need for your desired accuracy.