NAME¶

std::sin,std::sinf,std::sinl - std::sin,std::sinf,std::sinl

Synopsis¶

Defined in header <cmath>
float sin ( float arg );
float sinf( float arg ); (since C++11)
double sin ( double arg ); (1) (2)
long double sin ( long double arg );
long double sinl( long double arg ); (3) (since C++11)
double sin ( IntegralType arg ); (4) (since C++11)

1-3) Computes the sine 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).

Parameters¶

arg - value representing angle in radians, of a floating-point or Integral type

Return value¶

If no errors occur, the sine of arg (sin(arg)) in the range [-1 ; +1], 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.

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, it is returned unmodified
* if the argument is ±∞, NaN is returned and FE_INVALID is raised
* if the argument is NaN, NaN is returned

Notes¶

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

POSIX also specifies that in case of underflow, arg is returned unmodified, and if
that is not supported, an implementation-defined value no greater than DBL_MIN,
FLT_MIN, and LDBL_MIN is returned.

Example¶

// Run this code

#include <iostream>
#include <cmath>
#include <cerrno>
#include <cfenv>

#pragma STDC FENV_ACCESS ON
const double pi = std::acos(-1);
int main()
{
// typical usage
std::cout << "sin(pi/6) = " << std::sin(pi/6) << '\n'
<< "sin(pi/2) = " << std::sin(pi/2) << '\n'
<< "sin(-3*pi/4) = " << std::sin(-3*pi/4) << '\n';
// special values
std::cout << "sin(+0) = " << std::sin(0.0) << '\n'
<< "sin(-0) = " << std::sin(-0.0) << '\n';
// error handling
std::feclearexcept(FE_ALL_EXCEPT);
std::cout << "sin(INFINITY) = " << std::sin(INFINITY) << '\n';
if (std::fetestexcept(FE_INVALID))
std::cout << " FE_INVALID raised\n";
}

Possible output:¶

sin(pi/6) = 0.5
sin(pi/2) = 1
sin(-3*pi/4) = -0.707107
sin(+0) = 0
sin(-0) = -0
sin(INFINITY) = -nan
FE_INVALID raised

See also¶

cos
cosf computes cosine (\({\small\cos{x} }\)cos(x))
cosl (function)
(C++11)
(C++11)
tan
tanf computes tangent (\({\small\tan{x} }\)tan(x))
tanl (function)
(C++11)
(C++11)
asin
asinf computes arc sine (\({\small\arcsin{x} }\)arcsin(x))
asinl (function)
(C++11)
(C++11)
sin(std::complex) computes sine of a complex number (\({\small\sin{z} }\)sin(z))
(function template)
sin(std::valarray) applies the function std::sin to each element of valarray
(function template)