Calculate the tangent (tan and _tanl) and hyperbolic tangent (tanh and _tanhl).
#include <math.h>
double tan( double x );
double tanh( double x );
long double _tanl( long double x );
long double _tanhl( long double x );
| x | Angle in radians |
The tan functions return the tangent or hyperbolic tangent of their arguments. The list below describes the differences between the various tangent functions:
| Function | Description |
| tan | Calculates tangent of x |
| tanh | Calculates hyperbolic tangent of x |
| _tanl | Calculates tangent of x (80-bit version) |
| _tanhl | Calculates hyperbolic tangent of x (80-bit version) |
The _tanl and _tanhl functions are the 80-bit counterparts and use an 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.
The tan function returns the tangent of x. If x is large, a partial loss of significance in the result may occur; in this case, tan sets errno to ERANGE and generates a _PLOSS error. If x is so large that significance is totally lost, tan prints a _TLOSS error message to stderr, sets errno to ERANGE, and returns 0. Error handling can be modified by using the _matherr function.
There is no error return for tanh.
tan, tanh
Standards:ANSI, UNIX
16-Bit:DOS, QWIN, WIN, WIN DLL
32-Bit:DOS32X
_tanl, _tanhl
Standards:None
16-Bit:DOS, QWIN, WIN, WIN DLL
32-Bit:None
acos functions, asin functions, atan functions, cos functions, sin functions
/* 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", x, y );
printf( "tanh( %f ) = %f\n", y, x );
}
tan( 1.000000 ) = 0.761594
tanh( 0.761594 ) = 1.000000