[R] Loop on vector name

[Greg Snow]

Others have answered the question that you asked (it is also a variation of Faq 7.21), but here is an answer to the question that you should have asked:

When working with datasets like this, it is better to create a list rather than separate objects with names like dat1, dat2, etc.

For example:

> mydat <- list(dat1=rnorm(10), dat2=rnorm(25), dat3=runif(100))

Now your loop can be:

> for(i in 1:3) cat( sd( mydat[[i]] ) )

Or even simpler:

> sapply( mydat, sd )

And when you are through with the data, you only need to delete one object, or copy one object, or save one object, etc.

Hope this helps,


> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of Megh Dal
> Sent: Wednesday, September 17, 2008 5:51 AM
> To: r-help at stat.math.ethz.ch
> Subject: [R] Loop on vector name
>
> [My previous message rejected, therefore I am sending same one with
> some modification]
>
> I have 3 vectors with object name : dat1, dat2, dat3
>
> Now I want to create a loop, like :
>
> for (i in 1:3)
>    {
>     cat(sd(dati))
>    }
>
> How I can do this in R?
>
> Regards,
>
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