cos-cosf-cosl.md

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cos, cosf, cosl	API reference for cos, cosf, and cosl; which calculate the cosine value of a floating-point number.	08/31/2020	cos cosf cosl _o_cos _o_cosf	msvcrt.dll msvcr80.dll msvcr90.dll msvcr100.dll msvcr100_clr0400.dll msvcr110.dll msvcr110_clr0400.dll msvcr120.dll msvcr120_clr0400.dll ucrtbase.dll api-ms-win-crt-math-l1-1-0.dll	DLLExport	apiref	cos cosf cosl	cosines cosl function calculating cosine cosf function cos function trigonometric functions cosines, calculating	ae90435e-6b68-4a47-a81f-be87d5c08f16

cos, cosf, cosl

Calculates the cosine.

Syntax

double cos( double x );
float cosf( float x );
long double cosl( long double x );
#define cos(X) // Requires C11 or higher

float cos( float x );  // C++ only
long double cos( long double x );  // C++ only

Parameters

x
Angle in radians.

Return value

The cosine of x. If x is greater than or equal to 263, or less than or equal to -263, a loss of significance in the result occurs.

Input	SEH exception	_matherr exception
± QNaN, IND	none	_DOMAIN
± INF	INVALID	_DOMAIN

Remarks

Because C++ allows overloading, you can call overloads of cos that take and return float or long double values. In a C program, unless you're using the <tgmath.h> macro to call this function, cos always takes and returns a double.

If you use the <tgmath.h> cos() macro, the type of the argument determines which version of the function is selected. See Type-generic math for details.

By default, this function's global state is scoped to the application. To change this behavior, see Global state in the CRT.

Requirements

Routine	Required C header	Required C++ header
cos, cosh, cosf	<math.h>	<cmath> or <math.h>
cos() macro	<tgmath.h>

For more compatibility information, see Compatibility.

Example

See the example in sin, sinf, sinl.

See also

Math and floating-point support
acos, acosf, acosl
asin, asinf, asinl
atan, atanf, atanl, atan2, atan2f, atan2l
_matherr
sin, sinf, sinl
tan, tanf, tanl