function template
<valarray>

std::cos

template<class T> valarray<T> cos (const valarray<T>& x);
Compute cosine of valarray elements
Returns a valarray containing the cosines of all the elements of x, in the same order.

The function calls cos (unqualified) once for each element.

This function overloads cmath's cos.

Parameters

x
valarray containing elements of a type for which the unary function cos is defined. Each element's value represents an angle, expressed in radians.

Return value

A valarray object with the cosine values of the elements of x.

Example

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// cos valarray example
#include <iostream>     // std::cout
#include <cstddef>      // std::size_t
#include <cmath>        // std::cos(double)
#include <valarray>     // std::valarray, std::cos(valarray)

int main ()
{
  double val[] = {1.2, 3.14, 5.0};
  std::valarray<double> foo (val,3);

  std::valarray<double> bar = cos (foo);

  std::cout << "foo:";
  for (std::size_t i=0; i<foo.size(); ++i)
    std::cout << ' ' << foo[i];
  std::cout << '\n';

  std::cout << "bar: ";
  for (std::size_t i=0; i<bar.size(); ++i)
    std::cout << ' ' << bar[i];
  std::cout << '\n';

  return 0;
}

Output:

foo: 1.2 3.14 5
bar: 0.362358 -0.999999 0.283662


See also

cos (cmath)
Compute cosine (function)
sin
Compute sine of valarray elements (function template)
tan
Compute tangent of valarray elements (function template)