code: public double norm1()
      {
          double f = 0;
          for (int j = 0; j < n; j++)
          {
              double s = 0;
              for (int i = 0; i < m; i++)
              {
                  s += Math.abs(A[i][j]);
              }
              f = Math.max(f, s);
          }
          return f;
      }
docs: One norm
  
  @return maximum column sum.