Re: [tablix-list] Still got gaps...

From: Nicholas Robinson <>
Date: Fri Dec 03 2004 - 19:40:23 CET

On Friday 03 December 2004 09:45, Tomaz Solc wrote:
> Hash: SHA1
> | Running tablix, the timetable rapidly reaches a point where there are
> | no "sametime" errors, which I understand from reading the manual
> | means that there should be no gaps in the timetable even if some of
> | the lessons are scheduled to be in the same room at the same time.
> | Yet when I look at the output I get loads and loads and loads and
> | loads of gaps - far more than correspond to the number of timeplace
> | errors plus placecapability errors. I've checked and re-checked the
> | input file a dozen times and am as sure as I can be that there are no
> | errors.
> If "" module reports no errors that means that no students
> and no teachers have to be in two places in the same time. It does not
> care about gaps in the timetable.

I know, but my point is that if I've put in a total of 41 lessons for a class
and it has no sametime errors then I expect 41 lessons to appear in the
timetable even if some of the are scheduled to take place in rooms where
other classes are scheduled to take place at the same time.

> You have specified a number of conflicting restrictions: For example - a
> lot of subjects have this combination of restrictions:
> <restriction type="capability-place">field</restriction>
> <restriction type="preferred-room">JW</restriction>
> While classroom JW does not have a "field" capability. This means that
> you are ordering Tablix to do two things: a) schedule this subject in
> classroom JW and b) do not schedule this subject in classroom JW.
I had spotted this and removed it, but it didn't have any impact because if
you run tablix with -d 4 it says it Unknown subject restriction:
'preferred-room' because they should be in the <subject> within a <class>.

> Another example:
> <subject title="Games3" teacher="SH" perweek="1" room="Gamesfield 1">
> <restriction type="double-period">Games3</restriction>
> Another example:
><subject title="Games3" teacher="SH" perweek="1" room="Gamesfield 1">
><restriction type="double-period">Games3</restriction>

>This is obviously impossible to solve. This is not how "double-period"
>is used. Check the documentation. Also the "room" property is ignored in
>this case, because of specified "perweek".
I've taken all this out now but I had fixed room to read preferred-room and
found the typo Games3 which should have been Games4. If you look elsewhere in
the file I sent I have used it correctly in every other instance.

>Also I suggest removing all modules you do not use, because every module
>you specify in the XML file slows down Tablix.

At the moment I am using all the modules I have in the file but if I knock any
out henceforth I will do so - especially now I've discovered -d3 which gives
me the correct level of debug for this!

> In one of your previous mails, you mentioned that Tablix did not report
> an error even though two classrooms were not defined in the
> configuration. That is strange and maybe there is something wrong with
> your installation although I can't imagine what could cause Tablix to
> behave like this.

This was another 'preferred-room' in the subject definition rather than the
subject within class, so it was never actually checking the room existed
because it was throwing the restriction away (silently without -d3 or -d4).
You alerted me to the non-existent rooms in an earlier reply! I am slightly
relieved that you didn't spot the fact that it was in the wrong place
altogether! Somehow I don't feel so bad now!

> I suggest you read carefully through your configuration and remove all
> the errors I mentioned above. I'm sure you will also find some more. If
> you still have problems, send another mail with your new XML file and
> describe the problems you have with the attached file. It is hard to
> follow all your mails and while not having the exact configuration you
> are talking about.

All the errors you mention had been removed by the time I did my daily backup
24 hours ago. Obviously, I may have introduced some more since then, so I
will do as you say and re-check! Thanks for the offer to view it when I've
done so.

As an aside: Can I suggest that the 'subject' definition is changed to
something like 'can-teach' and leave 'subject' within 'class' as 'subject'?
The documentation is accurate but it sometimes easy to mistake which
'subject' is meant.

Thanks for all your help.

Best Wishes

Received on Fri Dec 03 19:48:52 2004

This archive was generated by hypermail 2.1.8 : Tue Aug 16 2005 - 20:42:33 CEST