[R] environments

[Antje]

Okay, I see, there is no really "easy" way (I was wondering whether I can set 
an environment as default for new created variables). Is there any difference 
if I call

myenv$myvar <- 10
or
assign("myvar",10, env=myenv)
?

Antje


Douglas Bates schrieb:
> On Tue, Aug 26, 2008 at 6:07 AM, Henrique Dallazuanna <wwwhsd at gmail.com> wrote:
>> I think you need assign, see ?assign for more details.
> 
>> On Tue, Aug 26, 2008 at 6:02 AM, Antje <niederlein-rstat at yahoo.de> wrote:
>>> Hi there,
> 
>>> I try to understand the usage of environments but I'm not sure if I get it.
>>> I wrote a test script like this:
> 
>>> testenv <- new.env(environment())
> 
>>> myfun <- function(x) {
>>>        print(testvar)
>>>        testenv$testvar_2 <- 20
>>> }
>>> environment(myfun) <- testenv
> 
>>> testenv$testvar <- 10
> 
> As Henrique said, the canonical way of assigning a value within an
> environment is the "assign".  A more obscure, but also more effective,
> approach is evalq which quotes an expression then evaluates it in the
> given environment.  For example
> 
>> env <- new.env()
>> evalq({aa <- 1:3; bb <- LETTERS[1:9]; cc <- list(A = aa, B = bb)}, env)
>> objects(env)
> [1] "aa" "bb" "cc"
>> env$aa
> [1] 1 2 3
> 
>>> myfun("hello")
>>> ls(envir = testenv)
>>>
>>> Now, I was wondering if there is any way to create new variables in my
>>> environment without this "testenv$...". I know that I can access it that way
>>> if I do an attach(testenv) before, but that does not help when creating new
>>> ones...
>>> Do I completely misunderstand the concept?
>>> I'm just looking for an elegant way to access objects of a graphical
>>> userinterface from each handler-function and so on. And I thought it might
>>> be good to pack them into an environment...
>>>
>>> Antje
>>>
>>> ______________________________________________
>>> R-help at r-project.org mailing list
>>> https://stat.ethz.ch/mailman/listinfo/r-help
>>> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
>>> and provide commented, minimal, self-contained, reproducible code.
>>>
>>
>>
>> --
>> Henrique Dallazuanna
>> Curitiba-Paraná-Brasil
>> 25° 25' 40" S 49° 16' 22" O
>>
>> ______________________________________________
>> R-help at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>>
>