|| || || || || || || ||

---

ApplyOrder.h

Go to the documentation of this file.

#ifndef Impala_Util_ApplyOrder_h
#define Impala_Util_ApplyOrder_h

#include "memory.h"

namespace Impala
{
namespace Util
{


template <class Type>
void
ApplyOrder(Type* data, const int* constOrder, int length)
{
    // order is copied to keep callers code simpler
    int* order = new int[length];
    memcpy(order, constOrder, length*sizeof(int));
    
    int i;
    for(i=0 ; i<length ; ++i)
    {
        if(order[i] != i)
        {
            // keep swapping until an element is put at the correct position (this will happen!)
            int indexFrom = i;
            int indexTo = order[i];
            order[i] = i;
            Type value = data[indexFrom];
            while(indexFrom != indexTo)
            {
                Type temp = data[indexTo];
                data[indexTo] = value;
                value = temp;
                indexFrom = indexTo;
                indexTo = order[indexFrom];
                order[indexFrom] = indexFrom;
            }
        }
    }
}

} // namespace Util
} // namespace Impala

#endif

---