与直方图相比，茎叶图更能细致的看出数据分布情况！

代码： 

> x<-c(25, 45, 50, 54, 55, 61, 64, 68, 72, 75, 75,
+ 78, 79, 81, 83, 84, 84, 84, 85, 86, 86, 86,
+ 87, 89, 89, 89, 90, 91, 91, 92, 100)
> stem(x)

The decimal point is 1 digit(s) to the right of the |

2 | 5
3 |
4 | 5
5 | 045
6 | 148
7 | 25589
8 | 1344456667999
9 | 0112
10 | 0