Fast 1/X division (reciprocal)

Question

Is there some way to improve reciprocal (division 1 over X) with respect to speed, if the precision is not crucial?

So, I need to calculate 1/X. Is there so

Answer 1

First, make sure this isn't a case of premature optimization. Do you know that this is your bottleneck?

As Mystical says, 1/x can be calculated very quickly. Make sure you're not using double datatype for either the 1 or the divisor. Floats are much faster.

That said, benchmark, benchmark, benchmark. Don't waste your time spending hours on numerical theory just to discover the source of the poor performance is IO access.