[R] Undefined columns selected

[Andrew Robinson]

Jennifer,

it looks like some of the columns that you are selecting don't exist.

What is the output of str(arc) before you run the code below?

Andrew

On Thu, Apr 28, 2011 at 04:49:41PM -0700, Jennifer Wessel wrote:
> This is part of my program.  I am getting an error, that I cannot figure  out, any help would very much appreciated, thanks.
> 
>  	# subset variables 
>  	arc <- arc[,c("SNAP", "code",  "ncode", "var", "n_total")]
> Error in `[.data.frame`(arc, , c("SNAP", "code", "ncode",  : 
>   undefined columns selected
>  	arc$N_eff <- with(arc, ifelse(var > 1, n_total, var * n_total))
> Error in storage.mode(test) <- "logical" : object 'var' not found
> 
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-- 
Andrew Robinson  
Program Manager, ACERA 
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