R help - Mar 2008 - How to turn a string into a variable name ?

Hi,

For example,

natural_nums <- 1:10
even_nums <- seq(2,10, by = 2)
types <- c("natural_nums", "even_nums")

What functions can be performed on types[1] to turn it into a variable name
and not a string ?

	[[alternative HTML version deleted]]

You may be looking for the get function.

See ?get

Ng Stanley wrote:
> Hi,
> 
> For example,
> 
> natural_nums <- 1:10
> even_nums <- seq(2,10, by = 2)
> types <- c("natural_nums", "even_nums")
> 
> What functions can be performed on types[1] to turn it into a variable name
> and not a string ?
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

I'm not sure why you would wish to do so, but it can be done:
> natural_nums <- 1:10
> even_nums <- seq(2,10, by = 2)
> types <- c("natural_nums", "even_nums")
> types <- lapply(types, as.name)  ## list of variable names
> types
[[1]]
natural_nums

[[2]]
even_nums
> eval(types[[1]])
 [1]  1  2  3  4  5  6  7  8  9 10
> eval(types[[2]])
[1]  2  4  6  8 10 


Bill Venables
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-----Original Message-----
From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org]
On Behalf Of Ng Stanley
Sent: Friday, 14 March 2008 1:27 PM
To: r-help
Subject: [R] How to turn a string into a variable name ?

Hi,

For example,

natural_nums <- 1:10
even_nums <- seq(2,10, by = 2)
types <- c("natural_nums", "even_nums")

What functions can be performed on types[1] to turn it into a variable
name
and not a string ?

	[[alternative HTML version deleted]]

______________________________________________
R-help at r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.