valarray::cshift


public member function
valarray<T> cshift (int n) const;

Cyclically shift elements

Returns a valarray with its elements rotated left n spaces (or right if n is negative).

The valarray returned has the same length as *this.

By cyclically shifting (rotating) an array, the I-th element in the resulting valarray corresponds to the element with position (I+n)%size() in the original valarray.

Unlike with valarray::shift, the valarray returned by cshift does not initialize new elements with their default constructor to fill the
last n elements in *this (or the first -n elements if n is negative). Instead, it uses the first (or last) elements of *this.

Parameters

n
Number of elements to rotate. If positive, it is rotated left. If negative, it is rotated right.


Return value

A valarray object with the elements of *this rotated n spaces.

Example

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// valarray::cshift example
#include <iostream>
#include <valarray>
using namespace std;

int main ()
{
  int init[]={10,20,30,40,50};

  valarray<int> myvalarray (init,5);   // 10 20 30 40 50
  myvalarray = myvalarray.cshift(2);   // 30 40 50 10 20
  myvalarray = myvalarray.cshift(-1);  // 20 30 40 50 10

  for (size_t n=0; n<myvalarray.size(); n++)
	  cout << myvalarray[n] << ' ';
  cout << endl;

  return 0;
}


Output:

20 30 40 50 10


See also

valarray::shift Shift elements (public member function)
valarray operators Valarray operators (functions)