[R] Memory not release when an environment is created

[luke-tierney at uiowa.edu]

My preference is to use a top level function in the package or global
env that takes as arguments just the variables I want in the parent
frame. That avoids the explicit environment manipulations. Here that
would be

> makeFunc0 <- function(xmin, xmax)
       function(y) (y - xmin) / (xmax - xmin)

> makeFunc1 <- function(x)
       makeFunc0(min(x), max(x))

> f <- makeFunc1(1:1e8)
> ls.str(all=TRUE, environment(f))
xmax :  int 100000000
xmin :  int 1
> parent.env(environment(f))
<environment: R_GlobalEnv>
> f(c(1234567, 2345678))
[1] 0.01234566 0.02345677

Best,

luke


On Thu, 22 Sep 2016, William Dunlap via R-help wrote:

> I like to have my function-returning functions use new.env(parent=XXX)
> to make an environment for the returned function and put into it only
> the objects needed by the function.  The 'XXX' should be a an environment
> which will hang around anyway.  It could be globalenv(), but if your
> function
> is in a package, as.environment(paste0("package:", .packageName))
> would work well.  The later ensures the your returned function has access
> to all the other functions in that package.
>
> E.g.,
>> makeFunc1 <- function(x) {
>    envir <- new.env(parent = environment(sys.function()))
>    envir$xmax <- max(x)
>    envir$xmin <- min(x)
>    with(envir, function(y) (y - xmin) / (xmax - xmin))
> }
>> f <- makeFunc1(1:1e8)
>> ls.str(all=TRUE, environment(f))
> xmax :  int 100000000
> xmin :  int 1
>> parent.env(environment(f))
> <environment: R_GlobalEnv>
>> f(c(1234567, 2345678))
> [1] 0.01234566 0.02345677
>
>
>
> Bill Dunlap
> TIBCO Software
> wdunlap tibco.com
>
> On Thu, Sep 22, 2016 at 8:41 AM, Olivier Merle <oliviermerle35 at gmail.com>
> wrote:
>
>> Dear,
>>
>> When I use big data for a temporary use it seems that the memory is not
>> released when a function/environement is created nearby.
>> Here the reproducible exemple:
>>
>> test<-function(){
>> x=matrix(0,50000,10000)
>> y=function(nb) nb^2
>> return(y)
>> }
>> xx=test() # 3 Go of Ram is used
>> gc() # Memory is not released !! even if x has been destroyed [look into
>> software mem used]
>> format(object.size(xx),units="auto") # 1.4 KiB => R is worng on the size
>> of
>> the object
>> rm(xx)
>> gc() # Memory is released
>>
>> ## Classic
>> test2<-function(){
>> x=matrix(0,50000,10000)
>> y=1
>> return(y)
>> }
>> xx=test2() # Memory is used
>> gc() # => Memory is released
>>
>> How can I release the data in test without destroying the xx object ? As x
>> which is big object is destroyed, I though I could get my memory back but
>> it seems that the function y is keeping the x object.
>>
>> Best
>>
>>         [[alternative HTML version deleted]]
>>
>> ______________________________________________
>> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
>> 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.
>>
>
> 	[[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.
>

-- 
Luke Tierney
Ralph E. Wareham Professor of Mathematical Sciences
University of Iowa                  Phone:             319-335-3386
Department of Statistics and        Fax:               319-335-3017
    Actuarial Science
241 Schaeffer Hall                  email:   luke-tierney at uiowa.edu
Iowa City, IA 52242                 WWW:  http://www.stat.uiowa.edu