cosh

Compute the hyperbolic cosine of the input radian.

Interface Definition

C interface:

float coshf(float x);

double cosh(double x);

long double coshl(long double x);

Fortran interface:

RES = COSHF(X);

RES = COSH(X);

Parameters

Parameter	Type	Description	Input/Output
x	For coshf, x is of single-precision floating-point type. For cosh, x is of double-precision floating-point type. For coshl, x is of long double-precision floating-point type.	Floating-point value of a radian angle.	Input

Return Value

The hyperbolic cosine y of the radian angle x is returned. y ∈ [1, +∞]
If the input is ±0, the return value is +1.
For coshf, when |x| ≥ 0x1.8p6 (96), the return value is +∞; when |x| ≤ 0x1p-13, the return value is 1.0.
For cosh, when |x| ≥ 0x1.8p9 (768), the return value is +∞; when |x| ≤ 0x1p-26, the return value is 1.0.
If the input is ±∞, the return value is +∞.
If the input is NaN, the return value is NaN.

Dependency

C: "km.h"

Examples

C interface:

   double pi = acos(-1); 
    // typical usage 
    double a = pi/3, b = pi/2, c = -3*pi/4, d = 0.0; 
    // special handling 
    double e = INFINITY, f = -INFINITY, g = NAN; 
    // print result 
    printf("cosh(pi/3) = %.15f\n", cosh(a)); 
    printf("cosh(pi/2) = %.15f\n", cosh(b)); 
    printf("cosh(-3*pi/4) = %.15f\n", cosh(c)); 
    printf("cosh(0.0) = %.15f\n", cosh(d)); 
    printf("cosh(INFINITY) = %.15f\n", cosh(e)); 
    printf("cosh(-INFINITY) = %.15f\n", cosh(f)); 
    printf("cosh(NAN) = %.15f\n", cosh(g)); 
    /* 
     *  cosh(pi/3) = 1.600286857702386 
     *  cosh(pi/2) = 2.509178478658057 
     *  cosh(-3*pi/4) = 5.322752149519959 
     *  cosh(0.0) = 1.000000000000000 
     *  cosh(INFINITY) = inf
     *  cosh(-INFINITY) = inf
     *  cosh(NAN) = nan 
     * 
     * */

Fortran interface:

    REAL(8) :: X = 0.0 
    PRINT*,  COSH(X) 
    ! 
    ! OUTPUT 
    !     1.000000000000000 
    !

Parent topic: Hyperbolic Functions