std::tanh, std::tanhf, std::tanhl
Defined in header <cmath> | ||
---|---|---|
(1) | ||
float tanh ( float arg ); | ||
float tanhf( float arg ); | (since C++11) | |
double tanh ( double arg ); | (2) | |
(3) | ||
long double tanh ( long double arg ); | ||
long double tanhl( long double arg ); | (since C++11) | |
double tanh ( IntegralType arg ); | (4) | (since C++11) |
1-3) Computes the hyperbolic tangent of
arg
4) A set of overloads or a function template accepting an argument of any integral type. Equivalent to 2) (the argument is cast to
double
).Parameters
arg | - | value of a floating-point or Integral type |
Return value
If no errors occur, the hyperbolic tangent ofarg
(tanh(arg), or earg -e-arg |
earg +e-arg |
If a range error occurs due to underflow, the correct result (after rounding) is returned.
Error handling
Errors are reported as specified in math_errhandling
.
If the implementation supports IEEE floating-point arithmetic (IEC 60559),
- if the argument is ±0, ±0 is returned
- If the argument is ±∞, ±1 is returned
- if the argument is NaN, NaN is returned
Notes
POSIX specifies that in case of underflow, arg
is returned unmodified, and if that is not supported, and implementation-defined value no greater than DBL_MIN, FLT_MIN, and LDBL_MIN is returned.
Examples
#include <iostream> #include <cmath> int main() { std::cout << "tanh(1) = " << std::tanh(1) << '\n' << "tanh(-1) = " << std::tanh(-1) << '\n' << "tanh(0.1)*sinh(0.2)-cosh(0.2) = " << std::tanh(0.1) * std::sinh(0.2) - std::cosh(0.2) << '\n'; // special values std::cout << "tanh(+0) = " << std::tanh(+0.0) << '\n' << "tanh(-0) = " << std::tanh(-0.0) << '\n'; }
Output:
tanh(1) = 0.761594 tanh(-1) = -0.761594 tanh(0.1)*sinh(0.2)-cosh(0.2) = -1 tanh(+0) = 0 tanh(-0) = -0
See also
(C++11)(C++11) | computes hyperbolic sine (sh(x)) (function) |
(C++11)(C++11) | computes hyperbolic cosine (ch(x)) (function) |
(C++11)(C++11)(C++11) | computes the inverse hyperbolic tangent (artanh(x)) (function) |
computes hyperbolic tangent of a complex number (function template) |
|
applies the function std::tanh to each element of valarray (function template) |
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