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# std::sin

From cppreference.com
< cpp‎ | numeric‎ | math

Defined in header `<cmath>` |  |
float sin( float arg ); | (1) |
double sin( double arg ); | (2) |
long double sin( long double arg ); | (3) |
double sin( Integral arg ); | (4) | (since C++11)

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).

### [edit] Parameters

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

### [edit] 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` is large | (until C++11)

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.

### [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, it is returned unmodified
- if the argument is ±∞, NaN is returned and FE_INVALID is raised
- if the argument is NaN, NaN is returned

### [edit] 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.

### [edit] 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

### [edit] See also

cos | computes cosine (cos(x)) (function) [edit]
tan | computes tangent (tan(x)) (function) [edit]
asin | computes arc sine (arcsin(x)) (function) [edit]
sin(std::complex) | computes sine of a complex number (sin(z)) (function template) [edit]
sin(std::valarray) | applies the function std::sin to each element of valarray (function template) [edit]
C documentation for sin

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