For comparison, these are the results I got from benchmarking this implementation with Rust's standard .sin() with a Core i3 M 380 (fast_sine is code from blog, normal_sine is .sin())
test fast_sine ... bench: 746,638 ns/iter (+/- 2,489)
test normal_sine ... bench: 1,535,147 ns/iter (+/- 13,731)
These ns/iter values seem crazy (a sin function that takes 1.5ms is just really bad). There is implicit loop when using Rust benchmark features, no need to put your own loops.
