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-rw-r--r--vendor/libm/src/math/cosh.rs39
1 files changed, 39 insertions, 0 deletions
diff --git a/vendor/libm/src/math/cosh.rs b/vendor/libm/src/math/cosh.rs
new file mode 100644
index 000000000..bac875566
--- /dev/null
+++ b/vendor/libm/src/math/cosh.rs
@@ -0,0 +1,39 @@
+use super::exp;
+use super::expm1;
+use super::k_expo2;
+
+/// Hyperbolic cosine (f64)
+///
+/// Computes the hyperbolic cosine of the argument x.
+/// Is defined as `(exp(x) + exp(-x))/2`
+/// Angles are specified in radians.
+#[inline]
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn cosh(mut x: f64) -> f64 {
+ /* |x| */
+ let mut ix = x.to_bits();
+ ix &= 0x7fffffffffffffff;
+ x = f64::from_bits(ix);
+ let w = ix >> 32;
+
+ /* |x| < log(2) */
+ if w < 0x3fe62e42 {
+ if w < 0x3ff00000 - (26 << 20) {
+ let x1p120 = f64::from_bits(0x4770000000000000);
+ force_eval!(x + x1p120);
+ return 1.;
+ }
+ let t = expm1(x); // exponential minus 1
+ return 1. + t * t / (2. * (1. + t));
+ }
+
+ /* |x| < log(DBL_MAX) */
+ if w < 0x40862e42 {
+ let t = exp(x);
+ /* note: if x>log(0x1p26) then the 1/t is not needed */
+ return 0.5 * (t + 1. / t);
+ }
+
+ /* |x| > log(DBL_MAX) or nan */
+ k_expo2(x)
+}