std::tan,std::tanf,std::tanl - std::tan,std::tanf,std::tanl
Defined in header <cmath>
float tan ( float arg );
float tanf( float arg ); (since C++11)
double tan ( double arg ); (1) (2)
long double tan ( long double arg );
long double tanl( long double arg ); (3) (since C++11)
double tan ( IntegralType arg ); (4) (since C++11)
1-3) Computes the tangent of arg (measured in radians).
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).
arg - value representing angle in radians, of a floating-point or
Integral type
If no errors occur, the tangent of arg (tan(arg)) is
returned.
The result may have little or no significance if the magnitude of arg
(until C++11)
is large
If a domain error occurs, an implementation-defined value is returned (NaN
where
supported)
If a range error occurs due to underflow, the correct result (after rounding)
is
returned.
Errors are reported as specified in math_errhandling.
If the implementation supports IEEE floating-point arithmetic (IEC
60559),
* if the argument is ±0, it is returned unmodified
* if the argument is ±∞, NaN is returned and FE_INVALID is
raised
* if the argument is NaN, NaN is returned
The case where the argument is infinite is not specified to be a
domain error in C
(to which C++ defers), but it is defined as a domain error in POSIX
The function has mathematical poles at π(1/2 + n); however no common
floating-point
representation is able to represent π/2 exactly, thus there is no
value of the
argument for which a pole error occurs.
// Run this code
#include <iostream>
#include <cmath>
#include <cerrno>
#include <cfenv>
// #pragma STDC FENV_ACCESS ON
const double pi = std::acos(-1); // or C++20's std::numbers::pi
int main()
{
// typical usage
std::cout << "tan(1*pi/4) = " << std::tan(1*pi/4)
<< '\n' // 45°
<< "tan(3*pi/4) = " << std::tan(3*pi/4) << '\n'
// 135°
<< "tan(5*pi/4) = " << std::tan(5*pi/4) << '\n'
// -135°
<< "tan(7*pi/4) = " << std::tan(7*pi/4) << '\n';
// -45°
// special values
std::cout << "tan(+0) = " << std::tan(0.0) <<
'\n'
<< "tan(-0) = " << std::tan(-0.0) << '\n';
// error handling
std::feclearexcept(FE_ALL_EXCEPT);
std::cout << "tan(INFINITY) = " << std::tan(INFINITY)
<< '\n';
if (std::fetestexcept(FE_INVALID))
std::cout << " FE_INVALID raised\n";
}
tan(1*pi/4) = 1
tan(3*pi/4) = -1
tan(5*pi/4) = 1
tan(7*pi/4) = -1
tan(+0) = 0
tan(-0) = -0
tan(INFINITY) = -nan
FE_INVALID raised
sin
sinf computes sine (\({\small\sin{x} }\)sin(x))
sinl (function)
(C++11)
(C++11)
cos
cosf computes cosine (\({\small\cos{x} }\)cos(x))
cosl (function)
(C++11)
(C++11)
atan
atanf computes arc tangent (\({\small\arctan{x} }\)arctan(x))
atanl (function)
(C++11)
(C++11)
tan(std::complex) computes tangent of a complex number (\({\small\tan{z}
}\)tan(z))
(function template)
tan(std::valarray) applies the function std::tan to each element of valarray
(function template)