[R] turn character string into unevaluated R object

Duncan Murdoch murdoch at stats.uwo.ca
Tue Mar 2 23:59:22 CET 2010

On 02/03/2010 5:42 PM, carol white wrote:
> Hi,
> How to turn a character string into an unevaluated R object? I want to load some files in a directory into data matrix R objects. I could do this with read.table and assign (see below). Then, I want to turn the character string representing a file name (the evaluated expression of i) into an unevaluated R object. Basically, I want to create matrices whose names are the same as the related file names.

I don't understand what you mean by an "unevaluated R object".  The code 
you give below looks as though it would do the rest of what you 
describe; what goes wrong with it?

> Chees,
> Carol
> ----------------------------
> suppose I have
> mat1, mat2, mat3 files
> v = list.files(".", all.files = F, pattern = "mat")
>  for (i in v)
> 	 assign(i, read.table(i, sep = "\t"), pos = 1)

I would leave off "pos = 1" here, though it should be harmless.  It will 
only make a difference if you execute this code inside a function or 
other local environment.

Duncan Murdoch

> then, I want to have 3 objects with the names mat1, mat2, mat3 containing what mat1, mat2, mat3 files contain.
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