[R] From Strings to Variable name. When get does not work

[Prof Brian Ripley]

On 12/03/2014 07:42, Alaios wrote:
> Hi all,
> I would like to turn some long strings like MyString$Myfield$MySubfield into variables but it looks like that the get does not like lists

Those are expressions not names, so you need to parse them.

 > eval(parse(text = "test$a"))
[1] 2

>
>
> so for example:
>
>   test<-list(a=2)
>
> test
>> $a
> [1] 2
>
>
> get("test")
>> $a
> [1] 2
>
>
> get("test$a")
>> Fehler in get("test$a") : Objekt 'test$a' nicht gefunden
>
> lapply(test,function(x) return (x$a))
>> Fehler in x$a : $ operator is invalid for atomic vectors
>
> What should I do to read those lists I have as strings?
>
> I would like to thank you in advance for your reply
>
> regards
> A
>
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>
>
>
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-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
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