Page 1 of 1

Set multiplication

Posted: Tue Apr 09, 2019 5:01 pm
by Hussain_TUT
Hello,

I am working in a model that produce one batch of a chemical process that has many sub-processes. The batch horizon is 700 time intervals. During the process, one process begin for short duration (10-50 interval) who beginning time and total duration is calculated by the optimization itself. The sub-process rate of reaction follows a trajectory that is saved in a parameter of size 50 interval (less than batch horizon). Now when this process activated, it should take the first value saved in the parameter rate(t1) and so on. I am using MIP programming where a binary variable sb_i(t) is used to indicate the beginning of the sub process. The constraint look like

set t /1*700/
set t1 /1*50/;
Parameter
rate(t1);
rate(t1)= (some different value)
;
Variable
sb_i(t);
Process_constraint(t);

process_constraint(t).. prcoess_mass(t)=E=process_mass(t-1)-[rate(t1)]*sb1(t);

But i think, direct way is not working due to vector different dimensions. So anybody has any idea how to proceed with such multiplication?

Thanks :)

Re: Set multiplication

Posted: Sat Jun 15, 2019 5:09 pm
by bussieck
I really did not get what you try to accomplish here. Write your model in mathematical notation and then the translation to GAMS is easy.

-Michael