程序输出，同一段数据，
用的是上面的代码
（和绘图时用的代码不一样）


Stage 1 Filtering
    Step 1/5
          OK
    Step 2/5
          OK
    Step 3/5
          OK
    Step 4/5
          OK
    Step 5/5
          OK
Stage 2 Pan-Tompkins
（进度省略）
Stage 3 Find peaks
100%
Marking Rwave
Stage 4 Statistic
The red line is bpm vs time
Max beats per second:70.8398
Min beats per second:48.5156
Average beats per second:60.2187