[Rd] sysdata.rda vs. rda files in data directory
groemping at beuth-hochschule.de
Sat Mar 23 18:12:54 CET 2013
my package FrF2.catlg128 holds large catalogues and is supposed to gain
additional ones. All the catalogues are intended for the user.
So far, the catalogues were stored in the data directory, and LazyData
was "no". I understand that this is not considered wise any more (if it
ever was), so that I want to change to LazyData "yes" with the next
release (which will also get some additional catalogues).
I have tried out using separate data files in the data directory (like
before) and one sysdata.rda file in the R directory (exporting all
catalogues from the namespace); there is a large difference in the
installed sizes between those two ways: the approach with sysdata.rda
uses only about half the size of the separate data files approach (5.6
Mb vs 11.7Mb).
As I would like to be able to query the available data in the package
via data(package="FrF2.catlg128")) even before the package is loaded, I
want to have a data directory with a datalist file in there. This
appears to be compatible with using a sysdata.rda file in the R
directory. (From a tidyness point of view, I would prefer the data file
to sit in the data directory as well; however, that about doubles the
installed size again (11.4 vs 5.6Mb) even if I use just the one
Regarding the installed package size, the best option is obviously one
sysdata.rda file in the R directory, but I want the datalist file for
the reason given above. A data directory without data files throws a
warning, so that I have to include a dummy data file (and documentation
for it) for allowing me to have a datalist file.
Finally my questions: Is there a better way to achieve what I am looking
for? And if not: is there any reason against combining a sysdata.rda
file in the R directory with a datalist file (that lists the data from
the sysdata.rda file) in the data directory, be it policy-wise or
perhaps in terms of memory usage within an R session?
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