cos


function
<cmath>
     double cos (      double x );
      float cos (       float x );
long double cos ( long double x );

Compute cosine

Returns the cosine of an angle of x radians.

In C++, this function is overloaded in <complex> and <valarray> (see complex cos and valarray cos).

Parameters

x
Floating point value representing an angle expressed in radians.


Return Value

Cosine of x.

Portability

In C, only the double version of this function exists with this name.

Example

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/* cos example */
#include <stdio.h>
#include <math.h>

#define PI 3.14159265

int main ()
{
  double param, result;
  param = 60.0;
  result = cos (param*PI/180);
  printf ("The cosine of %lf degrees is %lf.\n", param, result );
  return 0;
}


Output:

The cosine of 60.000000 degrees is 0.500000.


See also