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slice::slice

Defines a subset of a valarray that consists of a number of elements that are an equal distance apart and that start at a specified element.

slice( );
slice(
   size_t _StartIndex,
   size_t _Len, 
   size_t _Stride
);

Parameters

  • _StartIndex
    The valarray index of the first element in the subset.

  • _Len
    The number of elements in the subset.

  • _Stride
    The distance between elements in the subset.

Return Value

The default constructor stores zeros for the starting index, total length, and stride. The second constructor stores _StartIndex for the starting index, _Len for the total length, and _Stride for the stride.

Remarks

The stride may be negative.

Example

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

int main( )
{
   using namespace std;
   int i;

   valarray<int> va ( 20 ), vaResult;
   for ( i = 0 ; i < 20 ; i+=1 )
      va [ i ] =  2 * (i + 1 );

   cout << "The operand valarray va is:\n( ";
      for ( i = 0 ; i < 20 ; i++ )
         cout << va [ i ] << " ";
   cout << ")." << endl;

   slice vaSlice ( 1 , 7 , 3 );
   vaResult = va [ vaSlice ];

   cout << "\nThe slice of valarray va is vaResult:"
        << "\nva[slice( 1, 7, 3)] = ( ";
      for ( i = 0 ; i < 7 ; i++ )
         cout << vaResult [ i ] << " ";
   cout << ")." << endl;
}

The operand valarray va is:
( 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 ).

The slice of valarray va is vaResult:
va[slice( 1, 7, 3)] = ( 4 10 16 22 28 34 40 ).

Requirements

Header: <valarray>

Namespace: std

See Also

Concepts

slice Class

slice Members