3 replies to this topic

[ADMGYP]

Hello everyone,

I am quite confused, I need to do an optimization of a warehouse filling that depends on prices.
That is, when it is cheap I fill it and when it is expensive I take it out to sell, two types of restrictions must be met:
Have a minimum and maximum filling on specific dates and
the maximum and minimum value that the variable can take in injection or extraction:
Xi<0 extraction, Xi>0 injection.

The fact is that Xi has limits:

Xi<H

Where H is the maximum injection that can occur in one day and is calculated as:

MINIMUM between a constant and a function that depends on the filling the previous day:

Xi < H, where H= MIN (Constant, f(Vi-1)).

To eliminate functions like the Minimum, binary variables can be used, but for it to choose the minimum, I have to introduce non-linear conditions in the objetive function that the solver does not accept.

Do you know how I can solve this problem with some other software?

All the best,


ADM.

[Pilesar]

Does your software have an 'if' command? Nested 'if's can be ugly but seem to work.

[ADMGYP]

Hello pilesar,

Thanks, but I'm using OpenSolver which is an add-in and extension of excel solver that allows more variables and constraints.
I have tried with the IF but it detects that it is a non-linear model.

 

Thank you!

 

If anyone can give me a hand I would be very grateful.

[breizh]

Hi,

You may find pointers here :

https://cheguide.com...rogramming.html

Breizh