[R] How Can I Execute a String Expression?

[Bert Gunter]

eval(parse(text = yourstring))  # your string must be  quoted, because
that's what a string is.

But .... don't do this! (usually)

install.packages("fortunes") ## if not already downloaded and installed
library("fortunes")
fortune(106)

See ?substitute and ?bquote for perhaps better ways to proceed.

Cheers,
Bert
Bert Gunter

"The trouble with having an open mind is that people keep coming along
and sticking things into it."
-- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )


On Mon, Jun 12, 2017 at 6:55 PM, Donald Macnaughton <donmac at matstat.com> wrote:
> I have the string ggstr that I've built with string manipulation:
>
> ggstr =  "ggplot(df1, aes(x,y)) + geom_smooth(se=FALSE, span=0.01)"
>
> Assuming df1 is properly defined, this string will execute properly if I
> submit it manually without the quotes. How can execute the command as a
> string, so that I can run it repeatedly (with minor modifications) in a
> loop?  Presumably, it would be something like:
>
> execute(ggstr)
>
> Thanks for your help,
>
> Don Macnaughton
>
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