[R] Append Columns

[Adaikalavan Ramasamy]

Using append=TRUE in write.table only appends rows (see example below).
You might be interested in a recent tread about appending to save()
 http://tolstoy.newcastle.edu.au/R/help/04/07/1467.html

> write.table( matrix(1:9, 3), file="aaa.txt", sep="\t" )
> write.table( matrix(101:109, 3), file="aaa.txt", sep="\t",        
append=TRUE, col.names=FALSE )
> read.delim(file="aaa.txt", row.names=NULL)
  row.names  X1  X2  X3
1         1   1   4   7
2         2   2   5   8
3         3   3   6   9
4         1 101 104 107
5         2 102 105 108
6         3 103 106 109


Here are some possible solutions :

1) Read in the existing file first then use cbind and writing it back. 

2) If you plan on doing this frequently (as in a loop), transpose your
problem so that you appending rows as above and after the last
iteration, transpose the results.

3) If you have access to unix/linux environments you can try the paste
command.

Regards, Adai









On Sat, 2004-09-04 at 20:25, Yao, Minghua wrote:
> Dear all,
>  
> Can I use "write.table" to append columnns?
>  
> Thanks for any help
>  
> -MY
>  
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
>