std:: sin, std:: sinf, std:: sinl
|
Defined in header
<cmath>
|
||
| (1) | ||
|
float
sin
(
float
num
)
;
double
sin
(
double
num
)
;
|
(until C++23) | |
|
/* floating-point-type */
sin ( /* floating-point-type */ num ) ; |
(since C++23)
(constexpr since C++26) |
|
|
float
sinf
(
float
num
)
;
|
(2) |
(since C++11)
(constexpr since C++26) |
|
long
double
sinl
(
long
double
num
)
;
|
(3) |
(since C++11)
(constexpr since C++26) |
|
Additional overloads
(since C++11)
|
||
|
Defined in header
<cmath>
|
||
|
template
<
class
Integer
>
double sin ( Integer num ) ; |
(A) | (constexpr since C++26) |
std::sin
for all cv-unqualified floating-point types as the type of the parameter.
(since C++23)
|
A)
Additional overloads are provided for all integer types, which are treated as
double
.
|
(since C++11) |
Parameters
| num | - | floating-point or integer value representing angle in radians |
Return value
If no errors occur, the sine of
num
(
sin(num)
) in the range
[
-
1
,
+
1
]
, is returned.
|
The result may have little or no significance if the magnitude of num 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.
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, num 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.
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 :: sin ( num ) has the same effect as std :: sin ( static_cast < double > ( num ) ) .
Example
#include <cerrno> #include <cfenv> #include <cmath> #include <iomanip> #include <iostream> // #pragma STDC FENV_ACCESS ON const double pi = std::acos(-1); // or std::numbers::pi since C++20 constexpr double your_sin(double x) { double sin{0}, pow{x}; for (auto fac{1LLU}, n{1ULL}; n != 20; fac *= ++n, pow *= x) if (n & 1) sin += (n & 2 ? -pow : pow) / fac; return sin; } int main() { std::cout << std::setprecision(10) << std::showpos << "Typical usage:\n" << "std::sin(pi/6) = " << std::sin(pi / 6) << '\n' << "your sin(pi/6) = " << your_sin(pi / 6) << '\n' << "std::sin(pi/2) = " << std::sin(pi / 2) << '\n' << "your sin(pi/2) = " << your_sin(pi / 2) << '\n' << "std::sin(-3*pi/4) = " << std::sin(-3 * pi / 4) << '\n' << "your sin(-3*pi/4) = " << your_sin(-3 * pi / 4) << '\n' << "Special values:\n" << "std::sin(+0) = " << std::sin(0.0) << '\n' << "std::sin(-0) = " << std::sin(-0.0) << '\n'; // error handling std::feclearexcept(FE_ALL_EXCEPT); std::cout << "std::sin(INFINITY) = " << std::sin(INFINITY) << '\n'; if (std::fetestexcept(FE_INVALID)) std::cout << " FE_INVALID raised\n"; }
Possible output:
Typical usage:
std::sin(pi/6) = +0.5
your sin(pi/6) = +0.5
std::sin(pi/2) = +1
your sin(pi/2) = +1
std::sin(-3*pi/4) = -0.7071067812
your sin(-3*pi/4) = -0.7071067812
Special values:
std::sin(+0) = +0
std::sin(-0) = -0
std::sin(INFINITY) = -nan
FE_INVALID raised
See also
|
(C++11)
(C++11)
|
computes cosine (
cos(x)
)
(function) |
|
(C++11)
(C++11)
|
computes tangent (
tan(x)
)
(function) |
|
(C++11)
(C++11)
|
computes arc sine (
arcsin(x)
)
(function) |
|
computes sine of a complex number (
sin(z)
)
(function template) |
|
|
applies the function
std::sin
to each element of valarray
(function template) |
|
|
C documentation
for
sin
|
|