docs: public static void hist(float[] data, int fmax) {
  
          float[] hist = new float[data.length];
          // scale maximum
          float hmax = 0;
          for (int i = 0; i < data.length; i++) {
              hmax = Math.max(data[i], hmax);
          }
          float shrink = fmax / hmax;
          for (int i = 0; i < data.length; i++) {
              hist[i] = shrink * data[i];
          }
  
          NumberFormat nf = new DecimalFormat("00");
          String scale = "";
          for (int i = 1; i < fmax / 10 + 1; i++) {
              scale += "    .    " + i % 10;
          }
  
          System.out.println("x" + nf.format(hmax / fmax) + "\t0" + scale);
          for (int i = 0; i < hist.length; i++) {
              System.out.print(i + "\t|");
              for (int j = 0; j < Math.round(hist[i]); j++) {
                  if ((j + 1) % 10 == 0)
                      System.out.print("]");
                  else
                      System.out.print("|");
              }
              System.out.println();
          }
      }