code: public static double norm_inf(float[] a) {
      double max = Double.NEGATIVE_INFINITY;
      for (int i = 0; i < a.length; i++) {
        if (Math.abs(a[i]) > max) {
          max = Math.abs(a[i]);
        }
      }
      return max;
    }
docs: Computes inf-norm of vector
  
  @return inf-norm of a