public class SortingTools
{
   public static void SelectionSort(double[] a)
   {

      int i, j, min_j;          // Array indices
      double help;              // helper variable for 3-way exchange

      /* ---------------------------------------------------
         The selection sort algorithm
         --------------------------------------------------- */
      for ( i = 0 ; i < a.length ; i ++ )
      {
         /* ---------------------------------------------------
            Find array element with min. value among 
            a[i], a[i+1], ..., a[n-1]   
            --------------------------------------------------- */
         min_j = i;   // Assume elem i (a[i]) is the minimum
          
         for ( j = i+1 ; j < a.length ; j++ )               
         {
            if ( a[j] < a[min_j] )
            {
               min_j = j;    // We found a smaller minimum, update min_j
            }
         }
   
         /* ---------------------------------------------------
            Swap a[i] and a[min_j] 
            --------------------------------------------------- */
         help = a[i];
         a[i] = a[min_j];
         a[min_j] = help; 
      }
   }
}