Hello All
I am deep in to schedule territory and have a question for those souls
that have some experience in creating these beasts.

I have a schedule in place with instructors, classrooms & students,
the problem is that the students need to attend a preset number of
classes in a year , but they are not quite standard e.g student needs
to cover 10 classes for a subject over the course of a year (2 terms
Fall/Winter Sept - May) (these values are saved in a table and are
variable depending on subject)

I need to be able to apply the student to 10 classes on an even
distribution, currently they are being dropped into the schedule and
end up completing all 10 within a couple of months.

Looking for a strategy or suggestion on what may spread things out.

Thanks
John

Automating scheduling is one of the most complex tasks you can undertake,
because there are so almost-incredibly many possible combinations. Trying
to do it by "brute force" can lead to having to try so many combinations
that processing could be excessively long. As I'm not "expert" in this
area, I would be reluctant to try to make _any_ recommendations. Perhaps
someone with direct experience can provide you with some links.

--
Larry Linson, Microsoft Office Access MVP
Co-author: "Microsoft Access Small Business Solutions", published by Wiley
Access newsgroup support is alive and well in USENET
comp.databases.ms-access


"flymo" <fly_mo (AT) hotmail (DOT) com> wrote

On Jul 11, 2:31*pm, "Access Developer" <accde... (AT) gmail (DOT) com> wrote:
Thanks Larry

I am currently generating 20K records and it is probably 85% correct
and it does take a while (well over an hour) :-)

If someone with your experience is reluctant....I am so far out of my
depth.

#####
#### _\_ ________
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#( _\ | |------|
# __| | ||||||||
\ _/ | ||||||||
.--'--'-. | | ____ |
/ __ `|__|[o__o]|
_(____nm_______ /____\____


I will keep researching.
Cheers
John

In a recent issue of MSDN magazine, there was an article on using a bee
colony simulation to solve this kind of problem. What sticks in my mind is
that the sample they chose had 19 cities identified with the letters A - T,
gave the formula for determining the number of combinations (any time I see
the factorial sign !, I know somebody's about to overwhelm me) and that
computing all those paths on very fast, current technology, computers would
take hundreds of years.

I think I have disposed of that copy of the magazine, but if you can find
it, perhaps you could make good use of some or all of the techniques /
approaches they discuss. The examples were in C#, but I could follow them
with some help from the accompanying text. I chuckled when I imagined
naming a procedure or function "DoWaggleDance" in a production business
application -- of course it was just modeling what bees do in search of
sources of floral nectar.

--
Larry Linson, Microsoft Office Access MVP
Co-author: "Microsoft Access Small Business Solutions", published by Wiley
Access newsgroup support is alive and well in USENET
comp.databases.ms-access



"flymo" <fly_mo (AT) hotmail (DOT) com> wrote

On Jul 11, 2:31 pm, "Access Developer" <accde... (AT) gmail (DOT) com> wrote:
Thanks Larry

I am currently generating 20K records and it is probably 85% correct
and it does take a while (well over an hour) :-)

If someone with your experience is reluctant....I am so far out of my
depth.

#####
#### _\_ ________
##=-[.].]| \ \
#( _\ | |------|
# __| | ||||||||
\ _/ | ||||||||
.--'--'-. | | ____ |
/ __ `|__|[o__o]|
_(____nm_______ /____\____


I will keep researching.
Cheers
John

Hi John,

Nice drawing. Is that the output of your brain, trying to tackle your
scheduling problem?

Automatic scheduling is almost impossible. It is optimizing on a flat
surface with many relative small maxima, trying to find the "maximum
maximum".
The approach I would take on this moment is to describe the rules that
must be fullfilled, in terms of availability of teachers, students and
rooms, number of classes in time, packets of students, etc. etc.

Next step is to schedule, step by step, the things that have to be
schedeled, and check whether there is a conflict with the rules that
you have defined. Minor conflicts could mean a local optimization,
many conflicts mean your scheduling was a bad choice.
A few steps "could" be (via parameters) automated, e.g. the initial
spreading of the courses over the total available time, and filling
the courses with teachers and students.


In short, I would mostly invest in an easy-to-change-schedule and an
analyzing program that is run after each change of your "growing"
schedule to report the conflicts.

Imb.

On Jul 12, 6:17*am, imb <im... (AT) onsmail (DOT) nl> wrote:
Hi lmb

Yes my brain does feel like that (although when I had it in a word
does it looked more organised.....the pic , not my brain :-) )

I think I am getting as close as I can get (sort of where your "could
be" area is) without going in too deep . The records being generated
are close, I just need that extra tweak before I start editing them.
Then I can push to a master table and its live from there on.
I probably wont be the one managing the system once complete, so
making it user friendly and transparent are key requirements.

I appreciate the guidance, as I think if I can get this final
adjustment the rest is less complex. I already have a edit system
that forces swapping of records (action = reaction) so I avoid many
conflicts.

Regards
John

On Mon, 11 Jul 2011 08:25:52 -0700 (PDT), flymo <fly_mo (AT) hotmail (DOT) com>
wrote:

I'm thinking that if you had a list of the courses available and
randomly chose a date for the person in the time period. Then find
the previously scheduled course and slot them in.

See the RND function. Pay attention to the remarks about the
Randomize function otherwise the numbers generated won't be random.

You mention a year or 365 days. So multiple the single number
produced by Rnd by 365 and located the course date less than that
date.

Tony
--
Tony Toews, Microsoft Access MVP
Tony's Main MS Access pages - http://www.granite.ab.ca/accsmstr.htm
Tony's Microsoft Access Blog - http://msmvps.com/blogs/access/
For a convenient utility to keep your users FEs and other files
updated see http://www.autofeupdater.com/