Calculate the cosine (cos and _cosl) or hyperbolic cosine (cosh and _coshl).
#include <math.h>
double cos( double x );
double cosh( double x );
long double _cosl( long double x );
long double _coshl( long double x );
| x | Angle in radians |
The cos and cosh functions return the cosine and hyperbolic cosine, respectively, of x.
The _cosl and _coshl functions are the 80-bit counterparts and use the 80-bit, 10-byte coprocessor form of arguments and return values. See the reference page on the long double functions for more details on this data type.
If x is large, a partial loss of significance in the result may occur in a call to cos, in which case the function generates a _PLOSS error. If x is so large that significance is completely lost, cos prints a _TLOSS message to stderr and returns 0. In both cases, errno is set to ERANGE.
If the result is too large in a cosh call, the function returns HUGE_VAL and sets errno to ERANGE. This behavior can be changed with _matherr.
cos, cosh
Standards:ANSI, UNIX
16-Bit:DOS, QWIN, WIN, WIN DLL
32-Bit:DOS32X
_cosl, _coshl
Standards:None
16-Bit:DOS, QWIN, WIN, WIN DLL
32-Bit:None
acos functions, asin functions, atan functions, _matherr, sin functions, tan functions
/* 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 );
}
sin( 1.570796 ) = 1.000000
sinh( 1.570796 ) = 2.301299
cos( 1.570796 ) = 0.000000
cosh( 1.570796 ) = 2.509178