Optimization Tooling

Hi,I am working on a University Examination Timetabling Problem (UETP) using Binary Integer Programming, and I am running the model in AIMMS. The model is taking an unexpectedly long time to solve.Previously, I set the optimality relative tolerance to 0.01, and while the results were not 100% optimal, I was able to obtain optimal solutions in a reasonable amount of time. However, when I set the optimality relative tolerance to 0, the model has been running for an extended period. After 5 to 9 days, the gap was 0.38%, and after 10 to 16 days, the gap only reduced to 0.37%, this model still running.I ran this model on two different machines to compare performance, and both showed similar results:Server: Intel(R) Xeon(R) Silver 4214 CPU @ 2.20 GHz (2 processors), 16 GB RAM, Windows 10 Pro Desktop PC: 13th Gen Intel(R) Core(TM) i7-13700 @ 2.10 GHz, 64 GB RAM, Windows 11 ProMy questions are:What could be causing such a long execution time with this model? Are the specifications of these mac

This week, our partner CQM published a great use case on "valorization." The article is in Dutch, so I asked ChatGPT to translate it.https://cqm.nl/nl/cases/vips-maakt-planning-vion-datagedreven In agriculture, food production, and food processing industries, "valorization" is crucial. It increases the value, utility, or profitability of a product. In the meat processing industry, this means utilizing every part of the animal as efficiently as possible and making the most out of the meat. It’s a highly complex process with many variables. Together with meat producer Vion, CQM developed the VIPS application, which has made Vion's planning data-driven.Vion Food Group's largest production site is located in Boxtel. Vion is an international producer of meat, meat products, and plant-based alternatives. From this location, fresh meat and processed meat products are supplied to national and international retailers, food service industries, and the meat processing industry. Due to their scale

Hi, everyone! I’m trying to import a parameter based on a excel sheet. The cell is empty and the parameter is set with a default value of inf, but the parameter keep assuming value of zero. There’s anything that I can do to, if the cell is empty, the value assumed be different than zero?I don’t know if this should happen or if it’s an issue that has already been fixed. I’m using the verison 4.85, by the way. Thank you very much!

Hello! I was writting to see if anyone would be able to help me; you see, when I start up my AIMMS project file I get an error (which can be seen on the shared screenshot) about missing some kind of element in my project library. This started happening after moving my AIMMS project files from one computer to another, so I suspect that some data might not have transfered properly. In any case, I was hoping someone would be able to help me, as this is kind of urgent to be honest. Thank you very much in advance! Pablo

In the gantt chart, you can set a custom tooltip when the user is hovering over each of the jobs. Is it also possible to customize the tooltip that is shown when you modify one of the jobs? In one of my demos, it shows the following: but what I want in that tooltip is actually the current start and end times also (basically, my own custom string parameter) The same would be for not changing the size of the job, but dragging the position left-right. 

I have been trying to construct a optimal power flow(OPF) model. I refer to the OPF model in “How-to”, and add time terms( 24-hour optimisation cycles), energy storage and renewable generation to the model. However, there is an error of “The definition of constraint contains a goniometric function, which cannot be handled by BARON” in my model. This problem did not appear in the original model even though it also has geometric functions.Does anyone know why and how to avoid such errors? Thank you very much!

Can AIMMS achieve the function that copy one Section in Project A to Project B?  For example, there are two projects that need to use the energy storage model. I've built an energy storage module in Project A. How can I copy this module to Project B to avoid repetitive modeling？

I have an excel file with many spreadsheets. Almost all of them have tabular data information. But one of them has information like the image below. I read the documentation I found about dex, but I couldn't find out if it is possible to import using this format and how to do it.  

Hi community!Having installed AIMMS 24.4.3.3 (x64) on a new laptop running Windows 11, I am unable to select (latest version of) Chrome as the default browser for WebUI, even though Chrome is set as my default browser in Windows 11. I am a bit puzzled as to how to solve this issue. Any help is much appreciated here!In the pic below I haven’t been able to make a good screenshot but only Edge option is enabled, Chrome is disabled. Thanks! 

I have a table in WebUI which can be filtered through the table. The user can interact with the table to select rows associated with certain plants, for example. I would then like the user to be able to select a button to automatically check a check box for the visible rows. There could be many rows and selecting each row individually is not desired. How, in WebUI, can I tell which rows are visible after the user applies filters?

Hi! Does anyone know how to create a function with multiple inputs and outputs?For example, there is a function edited with MATLAB that :“function [ dP,dQ,Pi,Qi ] = Unbalanced( n,m,P,Q,U,G,B,cita )”. How to model this function in AIMMS? Thank you very much! 

I am trying to do some dataframe operation through AIMMS. I am giving some sample example. Say, only one row is there in a dataframe. The values are TC130 and SF520. Say the parameter name is ```pMap(tdc1, tdc2)```.  I would like to run a for loop on the second column value, i.e. on tdc2. Here it is SF520, I'll extract the corresponding value of SF520, which is TC130. Now I'll check in another dataframe, where quantity has been given for TC130. The parameter is ```p(tdc1)```.  If TC130 belongs to that dataframe, i.e. if p(tdc1) > 0 then I'll create a parameter on tdc2, say p(tdc2) and assign value 1 to that else 0.How to write this types of procudure in AIMMS. In a nutshell. I have two parameters p(tdc1, tdc2):= {(tdc1, tdc2) : 1} and p(tdc1):= {tdc1: quantity}. This is simple case.  

We have multiple projects and I’d like to use the same code (that i’m writing) for each project. In this code, ideally, it would write the Project Title to the database, along with some other data. How can I access that Project Title via the aimms code?

parameter Demo_Lab(c,l) is the element of c. So to declare the constraints, I insert this equation at the constraints definition.In this picture, I inserted the parameter in index domain of variables. So, I have question. What’s the differences between these two type of declaration? and what is the condition to use each of it. Can someone explain to me?

Hi,I basically need the corner coordinates of the visible map in the Map Widget. Please see the red dots below:  These coordinates will be needed when an action is triggered (e.g., a button is pressed), so they don’t need to be tracked continuously.Thanks.

I am using SetElementRename to rename one of my elements. However, each time I run the function, it claims that the element is specified in the model and cannot be renamed, but this element is not hard-coded in any part of the model.Has anyone actually got this function to work?

How can I revert an app on PRO back to it's original ( as designed by the developer ) layout? I know in the older versions of AIMMS you had the possibility to click on your name and you had the option to revert the layout: 4.44:   In newer versions of AIMMS I don't see this option anymore. Has this option been (re)moved? 4.71:  

Dear All,I want to apply an interpolation formula to determine the value of a parameter. For example, a parameter that states the emission limit to achieve a net zero emission system has a value in 2025 of 1000 tons of CO2 and in 2050 the emission target is 0. How do I fill in the emission value between 2025 and 2050?Thank you for the advice given.

Is it possible to get a list of the IP addresses from which AIMMS PRO Cloud calls would come?E.g. if in your model you are using DEX to make a call to a web API endpoint, what is the IP address / IP range it comes from?Knowing this address/range could be used to restrict the access to the API endpoint to only AIMMS PRO platform instead of opening it up to the complete internet (which would add an additional layer of security besides oauth2 authentication)

Dear all,I’m new to AIMMS WebUI. I don’t know why my browsers (Chrome and Edge) can not display the WebUI properly (the left panels).After creating the Widgets, I can not add them to the Pages.Would you please provide me some solutions?Best regards, 

Hi,Suppose I have a node set “Customers”. I would like to be able to select multiple customers (by drawing a circle around them or by selecting one by one using ctrl+click, etc.) and calculate the total demand (or do any action) for only the selected customers.Is there a way to do it?Thanks.

We have learned that app developers can improve efficiency by offering a single widget with multiple predefined views, rather than using multiple instances of the same widget for different data representations on a page.Introducing the Widget Named Views feature, initially introduced in AIMMS 4.95.1 and further enhanced in AIMMS 4.96.1, app developers now have the ability to create and provide various views of a widget.For instance, this feature allows you to offer a table view with one pivoting and another view with a different pivoting, all within the same widget. Additionally, you can even add a different widget type, such as a bar chart, as another view.App developers have the flexibility to specify the default view that users see when they first load the page. Furthermore, they can dynamically adjust the presented view based on user interactions with the app.When multiple named views are created for a widget, a new button is added to the widget's header section. By clicking on thi

Hi,I am solving a huge MIP (4446310 integer variables). I set the relative gap to 0% from CPLEX MIP settings. After 69532.16 sec (19.3 hours), the model stops running and the solver status says 'Terminated by solver' while the gap is 0.14%. Why does this happen? What are the possible causes? Thank you. Best regards,Wanie Saidi