[R] why is 9 after 10?

[Fox, John]

Dear Federico,

Might my.data[, 2] contain character data, which therefore would be sorted in this manner? For example:

> x <- sample(6:37, 1000, replace=TRUE)
> table(x)
x
 6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 
29 30 35 29 41 33 27 21 38 36 34 35 31 29 27 26 28 22 21 34 32 33 31 34 23 32 35 39 31 40 35 29 
> y <- as.character(x)
> table(y)
y
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37  6  7  8  9 
41 33 27 21 38 36 34 35 31 29 27 26 28 22 21 34 32 33 31 34 23 32 35 39 31 40 35 29 29 30 35 29

I hope this helps,
 John

-----------------------------
John Fox, Professor
McMaster University
Hamilton, Ontario
Canada L8S 4M4
Web: socserv.mcmaster.ca/jfox




> -----Original Message-----
> From: R-help [mailto:r-help-bounces at r-project.org] On Behalf Of Federico
> Calboli
> Sent: February 12, 2016 10:13 AM
> To: R Help <r-help at r-project.org>
> Subject: [R] why is 9 after 10?
> 
> Hi All,
> 
> I have some data, one of the columns is a bunch of numbers from 6 to 41.
> 
> table(my.data[,2])
> 
> returns
> 
>   10   11   12   13   14   15   16   17   18   19   20   21   22   23   24   25   26   27   28   29
> 30   31   32   33   34   35   36   37
> 1761 1782 1897 1749 1907 1797 1734 1810 1913 1988 1914 1822 1951 1973 1951
> 1947 2067 1967 1812 2119 1999 2086 2133 2081 2165 2365 2330 2340
>   38   39   40   41    6    7    8    9
> 2681 2905 3399 3941 1648 1690 1727 1668
> 
> whereas the reasonable expectation is that the numbers from 6 to 9 would
> come before 10 to 41.
> 
> How do I sort this incredibly silly behaviour so that my table follows a
> reasonable expectation that 9 comes before 10 (and so on and so forth)?
> 
> BW
> 
> F
> 
> --
> Federico Calboli
> Ecological Genetics Research Unit
> Department of Biosciences
> PO Box 65 (Biocenter 3, Viikinkaari 1)
> FIN-00014 University of Helsinki
> Finland
> 
> federico.calboli at helsinki.fi
> 
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-
> guide.html
> and provide commented, minimal, self-contained, reproducible code.