cosh

float       coshf( float arg );

double      cosh( double arg );

long double coshl( long double arg );

#define cosh( arg )

Parameters

Return value

If no errors occur, the hyperbolic cosine of arg (cosh(arg), or

) is returned.

If a range error due to overflow occurs, +HUGE_VAL, +HUGE_VALF, or +HUGE_VALL is returned.

Error handling

Errors are reported as specified in math_errhandling.

If the implementation supports IEEE floating-point arithmetic (IEC 60559),

• if the argument is ±0, 1 is returned
• If the argument is ±∞, +∞ is returned
• if the argument is NaN, NaN is returned

Notes

For the IEEE-compatible type double, if |arg| > 710.5, then cosh(arg) overflows.

Example

#include <stdio.h>
#include <math.h>
#include <errno.h>
#include <fenv.h>
 
#pragma STDC FENV_ACCESS ON
int main(void)
{
    printf("cosh(1) = %f\ncosh(-1)= %f\n", cosh(1), cosh(-1));
    printf("log(sinh(1) + cosh(1))=%f\n", log(sinh(1)+cosh(1)));
    // special values
    printf("cosh(+0) = %f\ncosh(-0) = %f\n", cosh(0.0), cosh(-0.0));
    // error handling 
    errno=0; feclearexcept(FE_ALL_EXCEPT);
    printf("cosh(710.5) = %f\n", cosh(710.5));
    if(errno == ERANGE) perror("    errno == ERANGE");
    if(fetestexcept(FE_OVERFLOW)) puts("    FE_OVERFLOW raised");
}

cosh(1) = 1.543081
cosh(-1)= 1.543081
log(sinh(1) + cosh(1))=1.000000
cosh(+0) = 1.000000
cosh(-0) = 1.000000
cosh(710.5) = inf
    errno == ERANGE: Numerical result out of range
    FE_OVERFLOW raised

References

• C11 standard (ISO/IEC 9899:2011):
  • 7.12.5.4 The cosh functions (p: 241)
  • 7.25 Type-generic math <tgmath.h> (p: 373-375)
  • F.10.2.4 The cosh functions (p: 520)
• C99 standard (ISO/IEC 9899:1999):
  • 7.12.5.4 The cosh functions (p: 222)
  • 7.22 Type-generic math <tgmath.h> (p: 335-337)
  • F.9.2.4 The cosh functions (p: 457)
• C89/C90 standard (ISO/IEC 9899:1990):
  • 4.5.3.1 The cosh function

See also