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tan (<valarray>)

Operates on the elements of an input valarray, returning a valarray whose elements are equal to the tangent of the elements of the input valarray.

template<class Type> 
   valarray<Type> tan( 
      const valarray<Type>& _Left 
   );

Parameters

  • _Left
    The input valarray whose elements are to be operated on by the member function.

Return Value

A valarray whose elements are equal to the tangent of the elements of the input valarray.

Example

// valarray_tan.cpp
// compile with: /EHsc
#include <valarray>
#include <iostream>
#include <iomanip>

int main( )
{
   using namespace std;
   double pi = 3.14159265359;
   int i;

   valarray<double> va1 ( 9 );
   for ( i = 0 ; i < 9 ; i++ ) 
      va1 [ i ] =  ( pi/2 ) * ( 0.25 * i - 1 );
   valarray<double> va2 ( 9 );

   cout << "The initial valarray is:\n";
   for ( i = 0 ; i < 9 ; i++ )
      cout << setw( 10 ) << va1 [ i ]
      << "     radians, which is   "
      << setw( 5 ) << ( 180/pi ) * va1 [ i ]
      << "   degrees" << endl;
   cout << endl;

   va2 = tan ( va1 );
   cout << "The tangent of the initial valarray is:\n ";
   for ( i = 0 ; i < 9 ; i++ )
      cout << va2 [ i ] << endl;
}

The initial valarray is: -1.5708 radians, which is -90 degrees -1.1781 radians, which is -67.5 degrees -0.785398 radians, which is -45 degrees -0.392699 radians, which is -22.5 degrees 0 radians, which is 0 degrees 0.392699 radians, which is 22.5 degrees 0.785398 radians, which is 45 degrees 1.1781 radians, which is 67.5 degrees 1.5708 radians, which is 90 degrees The tangent of the initial valarray is: 9.6701e+012 -2.41421 -1 -0.414214 0 0.414214 1 2.41421 -9.6701e+012

Requirements

Header: <valarray>

Namespace: std

See Also

Reference

Trigonometry Functions

Other Resources

<valarray> Members