Hi,
Please find below the gams equation with comments.
I have run the gams model but the phase precedence constraint is not working. For example phase 1 has to filled up before phase 2 and so on.
Equation:
LowPreceCons1(t).. sum(jp3,Ym(jp3,t)) -
sum(jp3,Qpm(jp3)*W(jp3+1,t))=G=0;
"this is the equation for precedence constraints, phase j1 has to be filled up before phase j2, then phase j3 will follow then phase j4 (its phase 1,2,3,4).
Qpm is the quantity of material in phase j.
W(j,t) is a binary variable (which is 1 = 1; if phase j is filled up in year t and 0;otherwise) whilst
Ym is total material moved from phase j during year t.
How do I let the equation above work since its more like a sequencing type of equation.
Kindly assist
Ike
Research Personnel
Precedence constraint
Precedence constraint
Last edited by ikeato 5 years ago, edited 1 time in total.
Re: Precedence constraint
Hi Ike
It is hard to say what the problem is as the syntax of this specific constraint looks fine.
Could you attach the model?
Cheers
Renger
It is hard to say what the problem is as the syntax of this specific constraint looks fine.
Could you attach the model?
Cheers
Renger
____________________________________
Enjoy modeling even more: Read my blog on modeling at The lazy economist
Enjoy modeling even more: Read my blog on modeling at The lazy economist
Re: Precedence constraint
Hi Renger,
Please find attached model.
Thanks,
Ike
Please find attached model.
Thanks,
Ike
Last edited by ikeato 5 years ago, edited 1 time in total.
Re: Precedence constraint
Sorry Ike, no idea to rewrite the equation.
Renger
Renger
____________________________________
Enjoy modeling even more: Read my blog on modeling at The lazy economist
Enjoy modeling even more: Read my blog on modeling at The lazy economist
Re: Precedence constraint
Hi Renger,
Thanks for the effort.
Please how do you write a normal gams equation to show that 1 should come before 2 then 3 then 4 in a given set j, whereby 1 with a quantity has to be filled up before 2 then 3 and 4?
Regards,
Ike.
Thanks for the effort.
Please how do you write a normal gams equation to show that 1 should come before 2 then 3 then 4 in a given set j, whereby 1 with a quantity has to be filled up before 2 then 3 and 4?
Regards,
Ike.