code: private double[][] createMatrix() {
          double time = 0;
          double tmin = 0;
          tmin = rainData[0][0];
          time = tmin;
          double[][] matrix = new double[nTime][networkPipes.length + 1];
  
          for( int i = 0; i < nTime; ++i ) {
              matrix[i][0] = time;
              time += dt;
          }
          return matrix;
      }
docs: /*
  Create the matrix which contains the result.