code: public double getValue(int index, double x, double y, double z) {
          double sum = 0;
          for (int i = 0; i < count_basis; i++)
              if (C.matrix[i][index] != 0d) sum += C.matrix[i][index] * basis.getValue(i, x, y, z);
          return sum;
      }
docs: Get the function value of a orbital at the position (x,y,z)