cos, cosh

Calculate the cosine (cos) or hyperbolic cosine (cosh).

double cos( double x );

double cosh( double x );

For additional compatibility information, see Compatibility in the Introduction.

Libraries

Return Value

The cos and cosh functions return the cosine and hyperbolic cosine, respectively, of x. If x is greater than or equal to 2⁶³, or less than or equal to –2⁶³, a loss of significance in the result of a call to cos occurs, in which case the function generates a _TLOSS error and returns an indefinite (same as a quiet NaN).

If the result is too large in a cosh call, the function returns HUGE_VAL and sets errno to ERANGE. You can modify error handling with _matherr.

Parameter

x

Angle in radians

Example

/* SINCOS.C: This program displays the sine, hyperbolic
 * sine, cosine, and hyperbolic cosine of pi / 2.
 */

#include <math.h>
#include <stdio.h>

void main( void )
{
   double pi = 3.1415926535;
   double x, y;

   x = pi / 2;
   y = sin( x );
   printf( "sin( %f ) = %f\n", x, y );
   y = sinh( x );
   printf( "sinh( %f ) = %f\n",x, y );
   y = cos( x );
   printf( "cos( %f ) = %f\n", x, y );
   y = cosh( x );
   printf( "cosh( %f ) = %f\n",x, y );
}

Output

sin( 1.570796 ) = 1.000000
sinh( 1.570796 ) = 2.301299
cos( 1.570796 ) = 0.000000
cosh( 1.570796 ) = 2.509178
 

Floating-Point Support Routines

See Also   acos, asin, atan, _matherr, sin, tan