acosh, acoshf, acoshl
The new home for Visual Studio documentation is Visual Studio 2017 Documentation on docs.microsoft.com.
The latest version of this topic can be found at acosh, acoshf, acoshl.
Calculates the inverse hyperbolic cosine.
double acosh( double x ); float acosh( float x ); // C++ only long double acosh( long double x ); // C++ only float acoshf( float x ); long double acoshl( long double x );
Parameters
x
Floating-point value.
The acosh functions return the inverse hyberbolic cosine (arc hyperbolic cosine) of x. These functions are valid over the domain x ≥ 1. If x is less than 1, errno is set to EDOM and the result is a quiet NaN. If x is a quiet NaN, indefinite, or infinity, the same value is returned.
| Input | SEH Exception | _matherr Exception |
|---|---|---|
| ± QNAN, IND, INF | none | none |
| x < 1 | none | none |
When you use C++, you can call overloads of acosh that take and return float or long double values. In a C program, acosh always takes and returns double.
| Function | C header | C++ header |
|---|---|---|
acosh, acoshf, acoshl | <math.h> | <cmath> |
For additional compatibility information, see Compatibility.
// crt_acosh.c
// Compile by using: cl /W4 crt_acosh.c
// This program displays the hyperbolic cosine of pi / 4
// and the arc hyperbolic cosine of the result.
#include <math.h>
#include <stdio.h>
int main( void )
{
double pi = 3.1415926535;
double x, y;
x = cosh( pi / 4 );
y = acosh( x );
printf( "cosh( %f ) = %f\n", pi/4, x );
printf( "acosh( %f ) = %f\n", x, y );
}
cosh( 0.785398 ) = 1.324609 acosh( 1.324609 ) = 0.785398
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.
Floating-Point Support
Long Double
cos, cosf, cosl, cosh, coshf, coshl
sin, sinf, sinl, sinh, sinhf, sinhl
asinh, asinhf, asinhl
tan, tanf, tanl, tanh, tanhf, tanhl
atanh, atanhf, atanhl
_CItan