[R] Working around 256 byte variable names? + trouble opening large file

[David Winsemius]

On Sep 21, 2009, at 4:04 PM, A Singh wrote:

> Dear R users,
>
> I am trying to read in a file with 105 columns, and when trying to  
> attach it, get an error as follows:
>
>> vc1<-read.table("P:\\R\\Everything-I.txt", header=T, sep=" ",  
>> dec=".",
> na.strings=NA, strip.white=T)
>> attach(vc1)
> Error in attach(vc1) : variable names are limited to 256 bytes
>
> Is there a way to get around this, and make R accept the given  
> variable names? Or will I have to shorten them?
>
It's my guess that you have an unmatched quote in your header  
somewhere. The error is reported when the length of a SINGLE variable  
name is over the 256 character limit, and not when the total number of  
characters in all of the variable names is over 256. Shirley, you  
cannot have a variable name that want to be that long.

> Also, when I try to read in a much larger file with 430 columns, I  
> get the error:
>
> Error in scan(file, what, nmax, sep, dec, quote, skip, nlines,  
> na.strings, :
> line 397 did not have 431 elements
>
> Is it that R isn't dealing too well with Excel-converted-to-text  
> files? Is it a function of file size?

R is not the problem. It is capable of "filling".

>
> I have double-checked the 430 column file and all data seems to be  
> in place.

Again, probably a misplaced quote character.

-- 

David Winsemius, MD
Heritage Laboratories
West Hartford, CT