Re: [R] ggplot2 argument handling odd

From: hadley wickham <h.wickham_at_gmail.com>
Date: Thu, 27 Mar 2008 07:57:35 -0500

> Ok, I will try that, thanks. BTW, where is this aes_string option
> documented, sounds useful? How could I do the same thing with facetting?
> If I want to save something like ". ~ groupVar" as a string in a
> variable, could I pass it with facet_string to ggplot?

It's a see also from ?aes (or at least it is in the development version). facet_grid should already accept a string instead of a function, so it should just work.

> But anyway, I would be curious how to do it with qplot. The basic
> question is: How to pass the string of a variable to a function which is
> supposed to interpret it. Aka:
>
> var <- "magicVar"
>
> fun(doSomeMagic(var))
>
> doSomeMagic should then write magicVar at the place.

In general, you can use as.name, substitute and eval:

x <- as.name("mpg")
y <- as.name("wt")

eval(substitute(qplot(x, y, data=mtcars), list(x=x, y=y)))

Hadley

-- 
http://had.co.nz/

______________________________________________
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.
Received on Thu 27 Mar 2008 - 16:51:21 GMT

Archive maintained by Robert King, hosted by the discipline of statistics at the University of Newcastle, Australia.
Archive generated by hypermail 2.2.0, at Mon 31 Mar 2008 - 08:30:24 GMT.

Mailing list information is available at https://stat.ethz.ch/mailman/listinfo/r-help. Please read the posting guide before posting to the list.

list of date sections of archive