[Oz] Generating

[Alain Ducharme]

Hello all,

Sorry to bother you yet again, but I have hit a wall
which I have been unable to climb. I am trying to
implement a specific constraint, and all my attempts
have been unsuccessful.

My problem is as follow. In a variant of the frequency
allocation problem (FAP), a set of N cells must each
receive a certain number of communication frequency.
For each pair of cells, an interference level is
given. A frequency F can be assign to a cell only if
the ratio between the signal and the sum of
interference levels coming from all the other cells
which have already been assigned the same frequency F
respects a certain threshold:

Sum(Interference) < Signal*Threshold

A set of binary variables indicates if frequency F is
assigned to cell C (x = 1) or not (x = 0)

What I have done is to create a procedure which
receives as parameters the identity of the cell being
considered and of one of the frequency being assigned
to it:

proc{Inter NumCell NumFreq}

The value of the signal is known, as is the value of
the interference level between any to cells. To
generate the constraint, the total interference level
caused by the cells having receive to same frequency
must be calculated. The result of the constraint would
be to exclude frequencies from the domain of certain
cells.

This can seems rather simple, but I have been unable
to translate that (successfully) into a procedure.

I hope I have been able to explain my problem clearly.
Does someone has an helpful suggestion?

Thank you all for your help,

Alain Ducharme



__________________________________________________
Do You Yahoo!?
Kick off your party with Yahoo! Invites.
http://invites.yahoo.com/
-
Please send submissions to users at mozart-oz.org
and administriva mail to users-request at mozart-oz.org.
The Mozart Oz web site is at http://www.mozart-oz.org/.