function template
<valarray>

std::acos

template<class T> valarray<T> acos (const valarray<T>& x);
Compute arc cosine of valarray elements
Returns a valarray containing the principal values of the arc cosine of all the elements of x, expressed in radians, in the same order.

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

This function overloads cmath's acos.

Parameters

x
valarray containing elements of a type for which the unary function acos is defined.

Return value

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

Example

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

int main ()
{
  double val[] = {0.0, 0.25, 0.5, 0.75, 1.0};
  std::valarray<double> foo (val,5);

  std::valarray<double> bar = acos (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: 0 0.25 0.5 0.75 1
bar: 1.5708 1.31812 1.0472 0.722734 0

See also

acos (cmath)
Compute arc cosine (function )
cos
Compute cosine of valarray elements (function template )
asin
Compute arc sine of valarray elements (function template )