[R] Access variables by string

[Philipp Rappold]

Dear all,

I have two probably very easy questions:

(1) Is there a way to access certain variables by their string-based 
name representation?

Example:
numbers <- c("one", "two", "three")
varname <- "numbers"
print(varname[2])

(2) I need this functionality for a customized na.exclude() function 
that I am building, which should only exclude rows that have NA in 
certain columns. Maybe there is already a function which does 
exactly what I need, so I'd highly appreciate if someone could point 
me there ;)

My current implementation looks like this:

naexlcude <- function(data, varnames)
{
	for(v in varnames){
		data = subset(data, !is.na(v))
	}

	data
}

Best
Philipp