Re: [R] From FAQ 7.21 to a command like apply(sapply(list(f1, f2, f3),, 2, sum)

From: Thomas Lumley <>
Date: Wed 30 Mar 2005 - 10:13:18 EST

On Wed, 30 Mar 2005, Heinz Tuechler wrote:

> Dear all,
> Last December there was a thread regarding the famous FAQ 7.21 "How can I
> turn a string into a variable?" and asking what people want to do with
> these strings.
> My, certainly trivial application would be as follows:
> Assume I have a data.frame containing besides others also the columns f1,
> f2, ..., fn and I want to create a command like:
> apply(sapply(list(f1,f2,f3),,2,sum)
> or
> summary(cbind(f1,f2,f3))
> Can I start from paste('f',1:3,sep='') to arrive at the abovementioned
> command?

No parse, or other complications needed. It's all just indexing. Suppose your data frame is called dd


         -thomas mailing list PLEASE do read the posting guide! Received on Wed Mar 30 10:25:15 2005

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