[R] A language technical question.

[Uwe Ligges]

Johan Lindberg wrote:

> If I have 100 objekts in a folder and I prefer not to load them manually 
> I wonder how I do this in R if using a for-loop.
> 
> I was thinking initially to do something like this:
> 
> infiles <- dir(pattern=".RData")

For sure you mean
   infiles <- dir(pattern = "\\.RData")


> for(i in length(infiles))

This won't work. I'd try
   for(i in 1:length(infiles))
or much better:
   for(i in seq(along = infiles))


>         {
>         load(infiles[i])
>         paste("kalle", i, sep="") <- saveLoadReference

Whatever saveLoadReference is ... try
   assign(paste("kalle", i, sep=""), saveLoadReference)

Please note that it might be a good idea to use a list "kalle" with 
elements corresponding to the different "saveLoadReference" objects. So 
that you don't mess up you workspace with many objects ....

Uwe Ligges


>         }
> 
> But the line """paste("kalle", i, sep="")""" does not do it for me. I 
> get the error message "Error: Target of assignment expands to 
> non-language object"
> 
> The thing that I do not master is how to create a name in a for-loop 
> that I can assign something to. And I want to be able to change that 
> name as the loop goes on. I want to create in this case
> kalle1
> kalle2
> kalle3
> ...
> kalle100
> 
> and they should all represent the objects that I opened with 
> load(infiles[i])
> 
> 
> Best regards
> 
> / Johan
> 
> 
> 
> ******************************************************************************************* 
> 
> Johan Lindberg
> Royal Institute of Technology
> AlbaNova University Center
> Stockholm Center for Physics, Astronomy and Biotechnology
> Department of Molecular Biotechnology
> 106 91 Stockholm, Sweden
> 
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