13 lines
233 B
V
13 lines
233 B
V
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module math
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[inline]
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pub fn q_rsqrt(x f64) f64 {
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x_half := 0.5 * x
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mut i := i64(f64_bits(x))
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i = 0x5fe6eb50c7b537a9 - (i >> 1)
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mut j := f64_from_bits(u64(i))
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j *= (1.5 - x_half * j * j)
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j *= (1.5 - x_half * j * j)
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return j
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}
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