The OpenD Programming Language

acosh

Calculates the inverse hyperbolic cosine of x.

Mathematically, acosh(x) = log(x + sqrt( x*x - 1))

$1 $2
Special Values
xacosh(x)
NaNNaN
<1NaN
10
+∞+∞
  1. real acosh(real x)
    @safe pure nothrow @nogc
    real
    acosh
    (
    real x
    )
  2. double acosh(double x)
  3. float acosh(float x)

Examples

import std.math.traits : isIdentical, isNaN;

assert(isNaN(acosh(0.9)));
assert(isNaN(acosh(real.nan)));
assert(isIdentical(acosh(1.0), 0.0));
assert(acosh(real.infinity) == real.infinity);
assert(isNaN(acosh(0.5)));

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