std::cosh, std::coshf, std::coshl - cppreference.com (original) (raw)

1-3) Computes the hyperbolic cosine of num. The library provides overloads of std::cosh for all cv-unqualified floating-point types as the type of the parameter.(since C++23)

[edit] Parameters

[edit] Return value

If no errors occur, the hyperbolic cosine of num (cosh(num), or ) is returned.

If a range error due to overflow occurs, +HUGE_VAL, +HUGE_VALF, or +HUGE_VALL is returned.

[edit] 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, 1 is returned.
• If the argument is ±∞, +∞ is returned.
• if the argument is NaN, NaN is returned.

[edit] Notes

For the IEEE-compatible type double, if |num| > 710.5, then std::cosh(num) overflows.

The additional overloads are not required to be provided exactly as (A). They only need to be sufficient to ensure that for their argument num of integer type, std::cosh(num) has the same effect as std::cosh(static_cast<double>(num)).

[edit] Example

#include #include #include #include #include // #pragma STDC FENV_ACCESS ON   int main() { const double x = 42;   std::cout << "cosh(1) = " << std::cosh(1) << '\n' << "cosh(-1) = " << std::cosh(-1) << '\n' << "log(sinh(" << x << ")+cosh(" << x << ")) = " << std::log(std::sinh(x) + std::cosh(x)) << '\n';   // special values std::cout << "cosh(+0) = " << std::cosh(0.0) << '\n' << "cosh(-0) = " << std::cosh(-0.0) << '\n';   // error handling errno=0; std::feclearexcept(FE_ALL_EXCEPT);   std::cout << "cosh(710.5) = " << std::cosh(710.5) << '\n';   if (errno == ERANGE) std::cout << " errno == ERANGE: " << std::strerror(errno) << '\n'; if (std::fetestexcept(FE_OVERFLOW)) std::cout << " FE_OVERFLOW raised\n"; }

Possible output:

cosh(1) = 1.54308 cosh(-1) = 1.54308 log(sinh(42)+cosh(42)) = 42 cosh(+0) = 1 cosh(-0) = 1 cosh(710.5) = inf errno == ERANGE: Numerical result out of range FE_OVERFLOW raised

[edit] See also