[R] paste data

[Hans-Joerg Bibiko]

On 18 Jun 2008, at 10:36, Sybille Wendel wrote:
> I need a command.
> I have a lot of data in different dataframes(auto.0a, auto.0b, auto. 
> 0c, auto.5Na,...), that has similar names.
>
> I could print the names all at once wih a loop with the command  
> paste(), see below:
>
> plot<- 
> c("0a","0b","0c","5Na","5Nb","5Nc","PKa","PKb","PKc","5NPKa","5NPKb",
> 	"5NPKc","10NPKa","10NPKb","10NPKc","20NPKa","20NPKb","20NPKc")
>
> for (x in 1:length(plot))
> {
> 	name<-paste("auto.",plot[x],sep="")
> 	print(name)
> }
>

First of all, maybe it is better to avoid to name a variable 'plot'.  
It works, but it could be a bit confusing.

You can do this easier (paste can handle vectors etc.):
name<-paste("auto.", plot, sep="")


> I want to do very similar things with all the dataframes and their  
> structure is also the same.
> Is there a way to write a loop? (so that I don't have to write the  
> same 18 times)
> I tried things like that:
>
> for (x in 1:length(plot))
> {
> 	plot(paste("auto.",plot[x],sep="")[,1],paste("auto.",plot[x],sep="") 
> [,2],col=...)
> }


paste("auto.",plot[x],sep="")[,1]  => doesn't work.

Assuming that 'auto.0a' is a data.frame you should use

get(paste("auto",".0a",sep=''))[,1]

instead to get the first column of the data.frame 'auto.0a'

Maybe try:

plot(get(paste("auto.",plot[x],sep=""))[,1],  
get(paste("auto.",plot[x],sep=""))[,2], col=...)

--Hans