R help - Jun 2010 - use a data frame whose name is stored as a string variable?

Hi,
Let's say I have a data frame (called "example") with numeric
values stored
(columns V1 and V2).  I also have a string variable storing this name

x1<-"example"

Is there a way to use the variable x so that R knows that I want the
specified action to occur on the data frame?  For example, summary (x) would
return a summary of the data frame?

I am considering this because I need to compare many data frames within 2
nested for loops.  In the first iteration of the loop I could concatenate x
and 1 and then use it to represent the data frame.  I'm open to a better
solution.  Thanks, Seth Myers 
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On Fri, Jun 25, 2010 at 5:10 PM, Seth <sjmyers at syr.edu>
wrote:
>
> Hi,
> Let's say I have a data frame (called "example") with numeric
values stored
> (columns V1 and V2). ?I also have a string variable storing this name
>
> x1<-"example"
>
> Is there a way to use the variable x so that R knows that I want the
> specified action to occur on the data frame? ?For example, summary (x)
would
> return a summary of the data frame?
?get

For example:

get(x) # one object
mget(x, envir=.GlobalEnv) # for multiple objects
## just change the environment if that is not where they are located
>
> I am considering this because I need to compare many data frames within 2
> nested for loops. ?In the first iteration of the loop I could concatenate x
> and 1 and then use it to represent the data frame. ?I'm open to a
better
> solution. ?Thanks, Seth Myers
It is hard to give a better solution without the rest of your code,
but there often are cleaner ways than for loops.  One solution that
avoids the character vector is to put the data frames together in
list.

Best regards,

Josh

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-- 
Joshua Wiley
Ph.D. Student, Health Psychology
University of California, Los Angeles
http://www.joshuawiley.com/

Thanks!  Works like a charm.  -Seth
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