[R-wiki] Summary of the discussion before creation of R-sig-wiki

[Philippe Grosjean]

Jonathan Baron wrote:
> On 01/18/06 11:33, Gabor Grothendieck wrote:
> 
>>Not sure if this changes anything but the version 4.0 beta of twiki claims
>>that it has "much simpler" installation:
>>
>>http://freshmeat.net/projects/twiki/?branch_id=46424&release_id=217318
> 
> 
> I believe that this was the version I installed.  I can help
> anyone who wants to try it.  But if this is "simpler" I hate to
> see what it was before.  Really it IS simple, but there are just 
> a few minor things that they don't tell you.  Like once it is
> actually alive, you do everything through TWiki itself.  The
> configuration page is just like any other page, and you edit it.
> Neat idea.  If they only told you!
> 
> Jon

Well, it seems that we have two contenders here: DokuWiki versus TWiki 
as possible engines for our R Wiki. So, I did a comparison of the two 
engines. Here is a summary, and the details come hereunder:

TWiki offers certainly more features than DokuWiki. Among those that are 
important in our context:
- Statistics: Twiki offers statistics about orphaned pages, most/least 
visited pages, recent visitors, etc., while DokuWiki offers only a list 
of recent changes. Note that there is a "stats" plugin in development 
for DokuWiki that tends to fill the gap (see: 
http://wiki.splitbrain.org/plugin:stats). Twiki wins.

- Formatting: Twiki allows for row spanning in table and for defining 
custom styles. However, DokuWiki allows right-to-left writting and 
footnotes that Twiki does not (all the rest could be added through 
plugins in one of the two engines, if needed). So, no clear winner here.

- Media revision/editing: DokuWiki allows only to add final versions of 
images and other media. TWiki is more flexible *but* what about the 
explosion of disk space used on the server with these additional 
features??? [personally, I think this is a point *against* Twiki, unless 
one can disable it!]. Twiki looses because of too much features?!

- Interface and style: DokuWiki is neat, intuitive and easier to use, in 
comparison to TWiki (well, this is a personal rating). This is a crucial 
point: remember that we want a maximum number of R users on the Wiki. If 
navigation or page edition is too difficult, it will discourage many 
potential users. DokuWiki wins (but is it really impartial?)

- Ease of installation: DokuWiki appears simpler (only need Apache + 
PHP). Whatever the installer, TWiki requires to install a lot more 
stuff. Not much a concern for the server (because this is done once and 
we have at least one knowledgeable people in the group), but what about 
packaging local versions of the Wiki that everyone could run on its own 
computer, deconnected from the Internet? DokuWiki wins, thus.

- The rest is, I think, details (PHP versus Perl, RCS or custom revision 
handling, links to sisterwiki, export in PDF, WYSIWYG edition, revision 
   diffs between any version, etc...).

So, my own conclusion: despite TWiki is a very powerful Wiki engine, I 
still prefer Dokuwiki. I will continue to work on my customized DokuWiki 
engine as a prototype for our R Wiki site. If someone else wants to 
start experiments with TWiki, I would be fine to reconsider the 
comparison on the basis of the two prototypes (but remember that you 
need to customize Twiki in order to offer something like R syntax 
coloring, nice equation rendering from the LaTeX definition in the .Rd 
files, etc. I am already two week ahead with the customization I have 
already done on DokuWiki ;-).
Best,

Philippe Grosjean

=== Here is the detailed comparison ================================

A comparison between DokuWiki and TWiki, using http://www.wikimatrix.org 
gives (I outline only the differences):

   * Engine: DokuWiki = PHP, TWiki = Perl
     Comment: this is personal, but I find PHP very intuitive... and can 
hardly read any perl code

   * Page storage: DokuWiki = plain text files, TWiki = RCS/Plain text 
files.
    Comment: I think plain text files is better than using a database, 
because it is easier to access from, let's say, an external R (recall 
that one idea is to change a little bit the Wikik syntax to embed it is 
R comments, so that a Wiki page could be sourced directly using 
source(). So, both are fine here. Twiki uses a regular RCS for saving 
versions of documents, while DokuWiki uses its own mechanism.

   * Requirements: DokuWiki = Apache + PHP, TWiki = a lot more.
     Comment: installation seems to be simplified in TWiki 0.4, and at 
least one knowledgeable people in our group (Jonathan Baron). So, not 
much of a problem?

   * Host Blocking: with a plugin in TWiki, not in DokuWiki

   * Revision diffs: DokuWiki = to current page, TWiki = between all
     Comment: personally, I consider any revision diff to another page 
than the current one as a useless gadget.

   * Right-to-Left support: Yes in DokuWiki, No in Twiki
     Comment: should we propose sections in other languages, this could 
be important for our eastern friends!

   * Page redirection: Yes in Twiki, No in DokuWiki
     Comment: ??? Since page redirection can be programmed with two 
lines of HTML or JavaScript and since DokuWiki supports writting of HTML 
embedded in Wiki pages, I don't understand why this is not possible in 
DokuWiki (may be not built-in,... but still possible if needed!)

   * Links to SisterWiki: Yes in Twiki, No in DokuWiki
     Comment: a link to sisterwiki is an automatic link to a page with 
the same name in another wiki site!!!??? I really don't see how useful 
this could be in our context!

   * Tables: Dokuwiki = simple, TWiki = simple + complex
     Comment: after looking at the table syntax in both engines, it 
appears that the only difference is "row spanning": in TWiki, you can 
make a cell spanning on multiple table rows, while you cannot do it with 
DokuWiki (in both cases, you can span a cell on multiple columns, define 
header style, align left/center/right very easily, etc.).

   * Footnotes: Yes in DokuWiki, No in TWiki

   * Custom styles and FAQ tags: No in DokuWiki, Yes in Twiki

   * WYSIWYG Editing: No in DokuWiki, optional in TWiki
     Comment: usually very slow (not tested in this case). The wikiwyg 
program in development will allow WYSIWYG editing in any Wiki engine 
very soon. So, not much a key point, I think.

   * Statistics: TWiki is more exhansitive: DokuWiki proposes only a 
list of recent changes. TWiki adds orphaned pages, most/least popular, 
recent visitors and analysis. This is a good point in favor of TWiki, 
certainly!

   * PDF export: No in DokuWiki, Yes in TWiki
     Comment: it is vital to export parts of our Wiki in PDF. DokuWiki 
proposes solutions (there is a page dedicated to this, but I don't 
remeber where). Also, I consider that existing feature in Wiki engines 
is not enough because they export one page at a time, with link to 
external wiki pages. We certainly want to export a whole namespace, or a 
given list of wiki pages into a compiled PDF manual with links inside 
the manual for related pages. As fas as I know, no Wiki engine does that 
yet. I don't know for TWiki, but I have already look at DokuWiki and it 
is rather flexible in the way exportations are defined. So, it is 
possible to program such a feature in the future if really needed.

   * Media revisions/image editing/media search: No in DokuWiki, Yes in 
TWiki
   Comment: personally, this is really a point *against* TWiki. Media 
(images, videos, sounds) take a lot of memory. I cannot imagine to keep 
the various versions of such media or other manipulation on large Wikis 
without exploding the disk space on the server required to store all the 
info (+ the backups). So, to summarize: saving an unlimited number of 
version for text documents: YES, doing the same for images: NO! Remember 
that our Wiki will start with: something like 3000+ pages of online help 
for all functions in CRAN & Bioconductor, 500+ pages for all packages, 
1500+ pages from converting "Statistics for R" + "Rtips" + "R Tcltk 
examples" (Statistics for R is already 1058 pages in PDF format)! So, 
this is going to be a very large Wiki!

   * Aligning text and text indentation: Yes in Twiki, No in DokuWiki
   Comment: well, if needed, there are plugins for that in DokuWiki (not 
correct in the wikimatrix table).

   * Ease of use (not in wikimatrix). This is something rather personal, 
but I have tried to navigate in TWiki and to figure out how I can find 
pages, create new pages, come back to previous ones, edit pages, etc. 
... and I find all this much less intuitive than in DokuWiki. Where is 
the simple "search" form? I see only a "jump" one, and obviously, you 
must type the name of a page, not some text to serach for in all pages. 
  There is no indication of the previous pages I visited to come back 
rapidly to them (a feature called "breadcrumbs" in DokuWiki, see 
http://wiki.splitbrain.org/wiki:breadcrumbs), the table of content in 
TWiki in on top of the page, while it is conveniently in a box at right 
in DokuWiki. This is just to cite a few...

   * Presentation: still very personal... but I really love the DokuWiki 
style. In comparison, TWiki one is too classical and boring. Of course, 
it is still possible to change the CSS file and customize the style.