v / vlib / math
Raw file | 12 loc (11 sloc) | 233 bytes | Latest commit hash 1cfc4198f 


1module math


2


3[inline]


4pub fn q_rsqrt(x f64) f64 {


5    x_half := 0.5 * x


6    mut i := i64(f64_bits(x))


7    i = 0x5fe6eb50c7b537a9 - (i >> 1)


8    mut j := f64_from_bits(u64(i))


9    j *= (1.5 - x_half * j * j)


10    j *= (1.5 - x_half * j * j)


11    return j


12}