1/// Absolute value (magnitude) (f64)
2///
3/// Calculates the absolute value (magnitude) of the argument `x`,
4/// by direct manipulation of the bit representation of `x`.
5#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
6pub fn fabs(x: f64) -> f64 {
7 select_implementation! {
8 name: fabs,
9 use_arch: all(target_arch = "wasm32", intrinsics_enabled),
10 args: x,
11 }
12
13 super::generic::fabs(x)
14}
15
16#[cfg(test)]
17mod tests {
18 use super::*;
19
20 #[test]
21 fn sanity_check() {
22 assert_eq!(fabs(-1.0), 1.0);
23 assert_eq!(fabs(2.8), 2.8);
24 }
25
26 /// The spec: https://en.cppreference.com/w/cpp/numeric/math/fabs
27 #[test]
28 fn spec_tests() {
29 assert!(fabs(f64::NAN).is_nan());
30 for f in [0.0, -0.0].iter().copied() {
31 assert_eq!(fabs(f), 0.0);
32 }
33 for f in [f64::INFINITY, f64::NEG_INFINITY].iter().copied() {
34 assert_eq!(fabs(f), f64::INFINITY);
35 }
36 }
37}
38