tan, tanh

Calculate the tangent (tan) or hyperbolic tangent (tanh).

doubletan(doublex**);**

doubletanh(doublex**);**

For additional compatibility information, see Compatibility in the Introduction.

Libraries

Return Value

tan returns the tangent 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 occurs, in which case the function generates a _TLOSS error and returns an indefinite (same as a quiet NaN). You can modify error handling with _matherr.

tanh returns the hyperbolic tangent of x. There is no error return.

Parameter

x

Angle in radians

Example

/* TAN.C:  This program displays the tangent of pi / 4
 * and the hyperbolic tangent of the result.
 */

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

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

   x = tan( pi / 4 );
   y = tanh( x );
   printf( "tan( %f ) = %f\n", pi/4, x );
   printf( "tanh( %f ) = %f\n", x, y );
}

Output

tan( 0.785398 ) = 1.000000
tanh( 1.000000 ) = 0.761594

Floating-Point Support Routines |  Long Double Routines

See Also   acos, asin, atan, cos, sin