code: public double get(int x, int y) {
      return (x == y) ? 0 : (x < y) //
          ? matrix[MatrixParadigm.triangleSize(y) + x] //
          : matrix[MatrixParadigm.triangleSize(x) + y];
    }
docs: Get a value from the (upper triangular) distance matrix.
  
  Note: in many cases, linear iteration over the matrix will be fastet than
  repeated calls to this method!
  
  @param x First object
  @param y Second object
  @return Distance