Dear All,
I am working on a function that has an optional data argument, just like lm().
If the user sets the data argument equal to some dataframe, then the function
should look inside the dataframe for the variables given to other arguments,
otherwise the variables should be accessible from what I believe is called the
parent frame from which the function was called. I looked at the source code
for lm() (and similar functions) and the documentation of ?eval, but I just
can't quite figure out how to make this work.
So, for a simple example, suppose I want to do this with the following function:
dosomething <- function(x, data) {
temp <- x^2 + 5
return(temp)
}
How does the function need to be changed, so that dosomething(somevariable,
data=somedataframe) will find somevariable within the dataframe somedataframe
and if dosomething(somevariable) is called, the function should find
somevariable in the parent frame (or anywhere else in the search path)?
Thanks for any help!
--
Wolfgang Viechtbauer
Department of Methodology and Statistics
University of Maastricht, The Netherlands
http://www.wvbauer.com/
______________________________________________
[email protected] 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.
