R help - Oct 2012 - problem in finding sizes of objects using a for loop

Dear All,

I wanted to extract the sizes of all created objects. For E.g when I
created 2 objects(x and y), I got their sizes using the following
code:
> x<-rnorm(10000)
> y<-runif(100,min=40,max=1000)
> ls()
[1] "x" "y"
> object.size(x)
80024 bytes
> object.size(y)
824 bytes

However, I was unable to get their sizes when I used a for loop in the
following way:
> objects<-ls()
> for (i in seq_along(objects)){
+   print(c(objects[i],object.size(objects[i])))
+
+ }
[1] "x"  "64"
[1] "y"  "64"


The result obtained by me is wrong in second case.

I understood that variables x and y are treated as characters. But to
rectify this problem.

Regards,
Purna

Dear Purna,

You need the get() function around object[i] in order to accomplish the
same results:

# data
x<-rnorm(10000)
y<-runif(100,min=40,max=1000)

# sizes
objects<-ls()
for (i in seq_along(objects)){
   print(c(objects[i],object.size(get(objects[i]))))  # get() is added here
 }
[1] "x"     "80040"
[1] "y"   "840"

get() is needed because each element of "objects" is a character and
the
object.size() function does not operates on characters, but on objects (not
your variable, the definition in R).  See ?get and ?object.size for more
information.

HTH,
Jorge.-


On Thu, Oct 25, 2012 at 5:24 PM, Purna chander <> wrote:
> Dear All,
>
> I wanted to extract the sizes of all created objects. For E.g when I
> created 2 objects(x and y), I got their sizes using the following
> code:
>
> > x<-rnorm(10000)
> > y<-runif(100,min=40,max=1000)
> > ls()
> [1] "x" "y"
> > object.size(x)
> 80024 bytes
> > object.size(y)
> 824 bytes
>
> However, I was unable to get their sizes when I used a for loop in the
> following way:
>
> > objects<-ls()
> > for (i in seq_along(objects)){
> +   print(c(objects[i],object.size(objects[i])))
> +
> + }
> [1] "x"  "64"
> [1] "y"  "64"
>
>
> The result obtained by me is wrong in second case.
>
> I understood that variables x and y are treated as characters. But to
> rectify this problem.
>
> Regards,
> Purna
>
> ______________________________________________
> R-help@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.
>
	[[alternative HTML version deleted]]

Hi,
?You can also use lapply() or sapply() without the get() function.

?list1<-list(x=x,y=y)
?sapply(list1,object.size)
#??? x???? y 
#80040?? 840 
?do.call(rbind,lapply(list1,object.size))
? # [,1]
#x 80040
#y?? 840

A.K.







----- Original Message -----
From: Jorge I Velez <jorgeivanvelez at gmail.com>
To: Purna chander <chanderbio at gmail.com>
Cc: r-help <r-help at r-project.org>
Sent: Thursday, October 25, 2012 2:40 AM
Subject: Re: [R] problem in finding sizes of objects using a for loop

Dear Purna,

You need the get() function around object[i] in order to accomplish the
same results:

# data
x<-rnorm(10000)
y<-runif(100,min=40,max=1000)

# sizes
objects<-ls()
for (i in seq_along(objects)){
?  print(c(objects[i],object.size(get(objects[i]))))? # get() is added here
}
[1] "x"? ?  "80040"
[1] "y"?  "840"

get() is needed because each element of "objects" is a character and
the
object.size() function does not operates on characters, but on objects (not
your variable, the definition in R).? See ?get and ?object.size for more
information.

HTH,
Jorge.-


On Thu, Oct 25, 2012 at 5:24 PM, Purna chander <> wrote:
> Dear All,
>
> I wanted to extract the sizes of all created objects. For E.g when I
> created 2 objects(x and y), I got their sizes using the following
> code:
>
> > x<-rnorm(10000)
> > y<-runif(100,min=40,max=1000)
> > ls()
> [1] "x" "y"
> > object.size(x)
> 80024 bytes
> > object.size(y)
> 824 bytes
>
> However, I was unable to get their sizes when I used a for loop in the
> following way:
>
> > objects<-ls()
> > for (i in seq_along(objects)){
> +?  print(c(objects[i],object.size(objects[i])))
> +
> + }
> [1] "x"? "64"
> [1] "y"? "64"
>
>
> The result obtained by me is wrong in second case.
>
> I understood that variables x and y are treated as characters. But to
> rectify this problem.
>
> Regards,
> Purna
>
> ______________________________________________
> 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.
>
??? [[alternative HTML version deleted]]

______________________________________________
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.

Here is a function I use to get the size of objects:

Here is an example output:
> my.ls()
                     Size     Mode
allStores       7,303,224     list
convertedStores         0     NULL
f.createCluster    40,508 function
x                  41,672     list
**Total         7,385,404  -------




my.ls <- function (pos = 1, sorted = FALSE, envir = as.environment(pos))
{
    .result <- sapply(ls(envir = envir, all.names = TRUE),
function(..x) object.size(eval(as.symbol(..x),
        envir = envir)))
    if (sorted) {
        .result <- rev(sort(.result))
    }
    .ls <- as.data.frame(rbind(as.matrix(.result), `**Total` = sum(.result)))
    names(.ls) <- "Size"
    .ls$Size <- formatC(.ls$Size, big.mark = ",", digits = 0,
        format = "f")
    .ls$Mode <- c(unlist(lapply(rownames(.ls)[-nrow(.ls)], function(x)
mode(eval(as.symbol(x),
        envir = envir)))), "-------")
    .ls
}


On Thu, Oct 25, 2012 at 2:24 AM, Purna chander <chanderbio at gmail.com>
wrote:
> Dear All,
>
> I wanted to extract the sizes of all created objects. For E.g when I
> created 2 objects(x and y), I got their sizes using the following
> code:
>
>> x<-rnorm(10000)
>> y<-runif(100,min=40,max=1000)
>> ls()
> [1] "x" "y"
>> object.size(x)
> 80024 bytes
>> object.size(y)
> 824 bytes
>
> However, I was unable to get their sizes when I used a for loop in the
> following way:
>
>> objects<-ls()
>> for (i in seq_along(objects)){
> +   print(c(objects[i],object.size(objects[i])))
> +
> + }
> [1] "x"  "64"
> [1] "y"  "64"
>
>
> The result obtained by me is wrong in second case.
>
> I understood that variables x and y are treated as characters. But to
> rectify this problem.
>
> Regards,
> Purna
>
> ______________________________________________
> 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.


-- 
Jim Holtman
Data Munger Guru

What is the problem that you are trying to solve?
Tell me what you want to do, not how you want to do it.