[R] Removing named objects using rm(..)

[Duncan Murdoch]

On 12-12-10 7:33 PM, Worik R wrote:
> Let me restate my question.
>
> Is there a straightforward way of ensuring I can use the variable name
> USDCHF?

You can use any legal variable name.  The only risk is that you will 
overwrite some other variable that you created.  You can't overwrite 
variables from packages.  (You might mask them, but they are still 
accessible using the :: notation.  E.g. after you set

USDCHF <- NULL

you can still access the one in timeSeries using

timeSeries::USDCHF


  Is there a straight forward way of ensuring that when I delete
> a variable by name I delete all copies in scope?

No.  It is not straightforward to delete any variables other than the 
ones that you created in the global environment.

Duncan Murdoch

>
> Worik
>
>
> On Tue, Dec 11, 2012 at 11:08 AM, Duncan Murdoch
> <murdoch.duncan at gmail.com <mailto:murdoch.duncan at gmail.com>> wrote:
>
>     On 12-12-10 4:40 PM, Worik R wrote:
>
>         When I import the library timeSeries I get (at least) the
>         variable USDCHF
>         imported too.
>
>         I would like to delete it, but I cannot.  As you can see below.
>
>
>     You didn't import timeSeries, you attached it.  It is on your search
>     list; you can see the full list using search().
>
>     The first item on the search list is .GlobalEnv, the user's global
>     environment.  You can create and delete items there.  You can't
>     easily do so in the other items in the search list, they are
>     essentially read-only.
>
>
>         Clearly I am doing something wrong.  What is it?
>
>
>     You need to learn more about how R does scoping.  I don't think the
>     description in the Intro to R is sufficient; you probably need the R
>     Language Definition discussion (or a third party book).
>
>     Duncan Murdoch
>
>
>             library(timeSeries)
>
>         Loading required package: timeDate
>
>             class(USDCHF)
>
>         [1] "timeSeries"
>         attr(,"package")
>         [1] "timeSeries"
>
>             rm(list=c("USDCHF"))
>
>         Warning message:
>         In rm(list = c("USDCHF")) : object 'USDCHF' not found
>
>             rm(USDCHF)
>
>         Warning message:
>         In rm(USDCHF) : object 'USDCHF' not found
>
>             class(USDCHF)
>
>         [1] "timeSeries"
>         attr(,"package")
>         [1] "timeSeries"
>
>
>
>         I can assign to it...
>
>             USDCHF<-NULL
>             class(USDCHF)
>
>         [1] "NULL"
>
>             get("USDCHF")
>
>         NULL
>
>
>
>
>         Worik
>
>                  [[alternative HTML version deleted]]
>
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>
>