diff options
Diffstat (limited to 'vendor/libm/src/math/exp10.rs')
-rw-r--r-- | vendor/libm/src/math/exp10.rs | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/vendor/libm/src/math/exp10.rs b/vendor/libm/src/math/exp10.rs new file mode 100644 index 000000000..9537f76f1 --- /dev/null +++ b/vendor/libm/src/math/exp10.rs @@ -0,0 +1,21 @@ +use super::{exp2, modf, pow}; + +const LN10: f64 = 3.32192809488736234787031942948939; +const P10: &[f64] = &[ + 1e-15, 1e-14, 1e-13, 1e-12, 1e-11, 1e-10, 1e-9, 1e-8, 1e-7, 1e-6, 1e-5, 1e-4, 1e-3, 1e-2, 1e-1, + 1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10, 1e11, 1e12, 1e13, 1e14, 1e15, +]; + +pub fn exp10(x: f64) -> f64 { + let (mut y, n) = modf(x); + let u: u64 = n.to_bits(); + /* fabs(n) < 16 without raising invalid on nan */ + if (u >> 52 & 0x7ff) < 0x3ff + 4 { + if y == 0.0 { + return P10[((n as isize) + 15) as usize]; + } + y = exp2(LN10 * y); + return y * P10[((n as isize) + 15) as usize]; + } + return pow(10.0, x); +} |