Hi Karl! Thanks for writing!

Doesn't this format require a column for a factor for every variable
present in any observation, whether or not that variable is present in the
observation in question? I think I end up with data that consists mainly of
columns of variables that are NAs for all but a few years.

But let me take a closer look at the data format and see.

Again, thanks! --andrewH


On Tue, Jan 15, 2013 at 9:22 AM, andrewH <ahoerner@rprogress.org> wrote:

> Dear Folks--
> Is there a data frame analog to sparse matrices? I am working with a panel
> data set that has a large number of variables that are redefined repeatedly
> or exist for only a few years (out of 48).  In my current structure, where
> variables are columns and rows are years, more than 90 percent of the cells
> and more than 3/4 of the total size of my file are NAs.
>
> I am wondering if there is an alternate file specification currently
> available that still allows numeric, character and factor data to be
> stored.
> Besides just using a database.
>
> A pointer in the right direction (or a solid "no" if that is the truth)
> would be greatly appreciated.
>
> Sincerely, andrewH
>
>
>
> --
> View this message in context:
> http://r.789695.n4.nabble.com/Sparse-dataframes-tp4655614.html
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
> 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.
>



-- 
J. Andrew Hoerner
Director, Sustainable Economics Program
Redefining Progress
(510) 507-4820

	[[alternative HTML version deleted]]

