# [Rd] "stem" does not give a correct answer (PR#9359)

Berwin A Turlach berwin at maths.uwa.edu.au
Mon Nov 13 07:16:18 CET 2006

```G' day Myung,

>>>>> "MGK" == mgkim  <mgkim at seowon.ac.kr> writes:

MGK> For the data c1 of size 14, stem provides the following result.

MGK> **************************************************************
>> c1
MGK> [1] 14 39 70 11 38 20 37 15 41 74 74 34 48 51
ZZangi> stem(c1)

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

MGK> 0 | 145
MGK> 2 | 04789
MGK> 4 | 181
MGK> 6 | 044

MGK> **************************************************************
MGK> However, stem does not give a correct answer, for example 34, 74, etc.

No bug, it is just the scale to which stem decides to plot by
default.  The line

4 | 181

should give a clue that this summarises 41, 48 and 51.  Since the data
is so sparse only even leading numbers are used.  Try:

> dat <- c(14, 39, 70, 11, 38, 20, 37, 15, 41, 74, 74, 34, 48, 51)
> stem(dat)

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

0 | 145
2 | 04789
4 | 181
6 | 044

> stem(dat, scale=2)

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

1 | 145
2 | 0
3 | 4789
4 | 18
5 | 1
6 |
7 | 044

Cheers,

Berwin