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sin (<valarray>)

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

template<class Type>
   valarray<Type> sin(
      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 sine of the elements of the input valarray.

Example

// valarray_sin.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 * ( 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 = sin ( va1 );
   cout << "The sine of the initial valarray is:\n";
   for ( i = 0 ; i < 9 ; i++ )
      cout << va2 [ i ] << endl;
}
The initial valarray is:
  -3.14159   radians, which is    -180   degrees
  -2.35619   radians, which is    -135   degrees
   -1.5708   radians, which is     -90   degrees
 -0.785398   radians, which is     -45   degrees
         0   radians, which is       0   degrees
  0.785398   radians, which is      45   degrees
    1.5708   radians, which is      90   degrees
   2.35619   radians, which is     135   degrees
   3.14159   radians, which is     180   degrees

The sine of the initial valarray is:
2.06823e-013
-0.707107
-1
-0.707107
0
0.707107
1
0.707107
-2.06823e-013

Requirements

Header: <valarray>

Namespace: std

See Also

Reference

Trigonometry Functions

Other Resources

<valarray> Members