1 /// Sign of Y, magnitude of X (f64)
2 ///
3 /// Constructs a number with the magnitude (absolute value) of its
4 /// first argument, `x`, and the sign of its second argument, `y`.
5 #[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
copysign(x: f64, y: f64) -> f646 pub fn copysign(x: f64, y: f64) -> f64 {
7     let mut ux = x.to_bits();
8     let uy = y.to_bits();
9     ux &= (!0) >> 1;
10     ux |= uy & (1 << 63);
11     f64::from_bits(ux)
12 }
13