Using zip format for help pages, examples, etc.
On 26 Mar 1999, Douglas Bates wrote:
"Jonathan" == Jonathan Rougier <J.C.Rougier@durham.ac.uk> writes:
Jonathan> On Fri, 26 Mar 1999, Martyn Plummer wrote:
>> The problem isn't that the help files take up a lot of space, but >> that certain file systems are extremely inefficient in the use of >> that space.
Jonathan> This is probably an unrealistic suggestion, but if Jonathan> compression is less of a problem than the number of files, Jonathan> why not take the help files `onboard' by creating a new Jonathan> class of objects with mode "help", which would be lists Jonathan> with components much like the current .Rd files, and Jonathan> attach them at the bottom of the search list. Each Jonathan> library would then require just a single file of help Jonathan> objects. This is a reasonable suggestion but I think that the way that R handles its search lists would make this problematic. At present objects in a library take up space in memory whether they are used or not. Also, the search to resolve a name is a linear search over the available names. Adding a whole lot more names for help objects would exacerbate both of those problems. Then there is the name-space pollution problem. Approaches to all of these issues with names and objects are being discussed and will probably be implemented in later releases. Right now I think the best approach to the problem of help files, etc. (other than waiting for certain commercial operating systems to catch up with concepts from the 1980's) is to use the zip format for the reasons that Brian Ripley indicated.
Doing this proved relatively easy and quite fast enough. It will appear in the next Windows version (rw0640, I presume) that is due in a few days. We just use unzip to extract a file and display it. (There is a DLL version of unzip, but it seems unnecessary.) Using zipped help is optional by package, and where selected (when installing the package from source) zips up the text, latex and example files. The space savings on a VFAT16 file system are considerable (about 20Mb on my system). It is a little unfair to blame Windows: it has had more space-efficient file systems (NTFS, FAT32) for some time. The problem is that not everything else (notably Linux) could read/write these, and so they were not the defaults. Brian
Brian D. Ripley, ripley@stats.ox.ac.uk Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272860 (secr) Oxford OX1 3TG, UK Fax: +44 1865 272595 -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-devel-request@stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._