NAME
tanh, tanhf
— hyperbolic tangent
function
LIBRARY
library “libm”
SYNOPSIS
#include
<math.h>
double
tanh(double
x);
float
tanhf(float
x);
DESCRIPTION
Thetanh()
and
tanhf()
functions compute the hyperbolic tangent of x. For a
discussion of error due to roundoff, see
math(3).
RETURN VALUES
Upon successful completion, these functions return the hyperbolic tangent value. The following may also occur:
- If x is ± 0, x is returned.
- If x is NaN, a NaN is returned.
- If x is positive infinity, a value 1 is returned; if x is negative infinity, -1 is returned.
- If x is subnormal, a range error can occur and x is returned.
SEE ALSO
acos(3), asin(3), atan(3), atan2(3), cos(3), cosh(3), math(3), sin(3), sinh(3), tan(3)
STANDARDS
The described functions conform to ISO/IEC 9899:1999 (“ISO C99”).