[R] converting strings to expressions

[Peter Dalgaard]

"Deepayan Sarkar" <deepayan.sarkar at gmail.com> writes:

> Hi,
> 
> consider this:
> 
> --------------
> 
> estr <- c("2^4", "alpha[1]")
> eexp <- expression(2^4, alpha[1])
> 
> 
> ## Is it possible to get 'eexp' starting from 'estr'? The closest I could
> ## get was:
> 
> do.call(expression, lapply(estr, as.name))
> 
> ## but it is not quite the same; e.g. the following behave differently:

Er, how about

> estr <- c("2^4", "alpha[1]")
> parse(text=estr)
expression(2^4, alpha[1])

or (brain teaser alert!)

> parse(text=deparse(parse(text=estr)))[[1]]
expression(2^4, alpha[1])

which is _not_ quite the same thing.

-- 
   O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
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