Optimization Tooling

Hey everyone, I´m currently using Aimms to build a model for my Bachelor Thesis. I have never worked with Aimms before so I´m pretty clueless in some regard.   So my problem is the following constraint: sum [i, aSP(h,i)*x(i,t)] + sum [j, sum [m, aFP(h,m)*(y(j,m,t))]] <= Capacity(h)   Here x(i,t) and y(j,m,t) are the decision variables which represent the accepted requests for two Product types. i are the different types of Product x and j are different types for Product y. t stands for different Periods. aSP and aFP indicate if product x(i) or y(j) needs Ressource h for its production. I have declared Capacity(h) as a parameter with values for each h. My Problem is now that the Programm takes these values for each seperate period, but the capacity in period 2 is of course lower than the capacity in period 1 and so on. I also cant just declare Capacity parameters for each period, because the remaining capacity in the periods

I have several problems but I think they are related to each other. For all my constraints I get the warning “The index “i” already has a scope” and I also get this warning when I want to enter my data. Also when I want to specify the objective for my Mathematical Program I get the warning: “Expecting a scalar identifier (no free indices)”. I’ve added pictures of one of my constraints, the warning from the Mathematical Program and my Set where I believe the problem might be with the index i. But I don’t really know how to fix it so if someone could help me I would be very grateful. 

Hello All!I wanted to start a thread in the community to discuss implementations and solutions to the Kaggle X-Mas challenge. For those of you who don’t know, Kaggle it is a site intended for promoting data science through courses and challenges. Every X-Mas they have a special optimization challenge. You can find more information below on this years challenge in the link below:https://www.kaggle.com/c/santa-2021/overviewA quick summary is: “Santa is creating a new streaming service and will play a 24/7 loop of 7 films. He would like the showing sequence to be optimal. Hence 3 groups of elves are watching all possible sequences (7! = 5040) of 7 movies to evaluate what is the best sequence.So, it has to do with permutations and TSP’s. Permutations, because we need to identify all possible combinations of sequences. And TSP’s because the problem can be trans

Hello everyone. I have been looking to solve a train scheduling problem using bilevel optimization. In this problem, two conflicting objectives are considered: the operator’s and the passengers’, having the passengers’ optimization problem nested inside the operator’s optimization problem (as a constraint). Is it possible to model this type of bilevel optimization problem? If not, are there other approaches using stackelberg games that can be considered? Thank you very much.

Hi, so with the ArgMax function I can find the maximum value out of a Parameter of numbers like this: ArgMax(i, SomeParamter(i))   However I would like to find the maximum value in a 2-dimensional Paramter. So ideally I would like to do something like this: ArgMax((i,j), Some2DimensionalParamter(i,j)) This is not possible though, because apperently only one index is permitted for the iterative operator argmax. Does anyone have an idea how this could be done?   Thank you!

Hello,    I have a set of 30 Customers, {1,2,...30}. I want to create subsets of these customers. Specifically, I want to get subsets with cardinality 1,2 and 3. These sets combined should then form the set ‘Routes’, such that the set ‘Routes’  looks as follows: {1}, {2}, … , {30}, {1,2}, {1,3},… { 29,30}, {1,2,3} , {1,2,4} ….. So the idea is to obtain routes containing 1,2 or 3 customers.   I would really appreciate some hints about implementing this in AIMMS.  Thank you in advance.   

In your answer to my previous question, you mentioned I could keep the questions coming. Last couple of days I have been playing quite a bit with AIMMS and the WebUI again, so here are some of my questions @Pratap Kumble  . In the winUI, I had the option of denoting a string parameter that should be used for the display of the values of an index of a parameter in the pivottable. For example, my set could be elements {0,1,2} but I could set a string parameter to be used to display the values of the set, meaning in the table it would be shown as { “My option 1”, “My option 2”, “My option 3” } Is this still easily possible and am I overlooking something, or is this option not possible anymore? One of the options I liked in the winUI is setting the columns to auto-width based on the data that was displ

The innovation  In order to provide additional security for our licensing database, we have enabled encrypted connection to it from your AIMMS applications and from the AIMMS License Server. Who does it affect and how?Users of AIMMS versions older than 4.66 and users of AIMMS License Server version older than 4.0.0.66, including for PRO on premise (no impact on AIMMS Cloud). These two groups of products will not be immediately able to establish connection with the AIMMS licensing database.Further to our License Agreement, for licenses activated as personal nodelocks , AIMMS will try to connect to the database on every usage. If there are more than 60 days without this connection being established the license will get locked.For licenses activated as machine nod

Hi,I am working on a project of delivery planning.In my model i have a constraint which defines the Unavailability of a vehicle for some time due to maintenance or already on a delivery. The Time a vehicle becomes unavailable is a parameter.the constraint is :Here,X_v,t → indicator variable for maintenance(whether need to go for maintenance)S(v) → time required for maintenance of vehicle v status_v,t → indicator variable for availability of vehicle v on day t   I am unable to write it in AIMMS. how to get the range of tau ?i was able to get the range for a single value parameter h using SubRange function                             tau

Hi. I am trying a generate a plot of optimality gap vs solution time. For that, I am trying to retrieve incumbent solution, best bound and solution time after every 5 iterations. But, for some reason, I am having issues with callback and I don’t get anything retrieved. Attached herewith are the images giving implementation of callback operation. Could anyone please tell where I am going wrong? Thanks,  Sujit

In converting WinUI to WebUI, I have to convert the popups. Seemingly no problem, right?It is a bit annoying, but fairly easy to do. Here’s the conversion...Old (WinUI) way:pr_DoStuffsp_Answer := DialogAsk(“Here’s a question”, “Yes”, “No”);if sp_Answer = “Yes” then do this elseif sp_Answer = “No” then do that endif; New (WebUI) way (with TWO procedures):pr_DoStuffwinui::RequestPerformDialogWebUI(“”, “Here’s a question”, s_ButtonActions_YesNo, ‘pr_DoNextStuff’); pr_DoNextStuff(sp_Answer) code isif sp_Answer = “Yes” then do this elseif sp_Answer = “No” then do that endif; HOWEVER, in the case of the Logoff Procedure, this doesn’t work. Specifically, I want to ask the user if they want to save the changed data, wait for them to respond, then save (or not) and close. Old (WinUI)

Hi AIMMS community,I am having problems to activate my academic license. This error reported by AIMMS:Logging on to AIMMS License Server failed: No logon response from serverAny ideas on how to solve it? 

Hi there! My question is fairly simple: how should we handle conflicts in the .nch file when merging different branches in a version control system? When two branches originate from the same commit, and namechanges are made, the .nch file contains new lines at exaclty the same line numbers, often (always) resulting in conflicts. Currenlty I resolve these by resolving the conflicts with "mine before theirs” as I tend to want to keep both. The need for this (simple) manual intervention is a bit annoying. What are the alternatives? Could we even simply ignore the .nch file in our git repository? Is there a way to track the file but prevent conflicts? I would like to hear your thoughts!

Dear All, I have been trying to use ellipsoid uncertainty in a simple problem that I have.The problem is an assortment optimization. Then, I have the Demand Mean for each products Dem(p) and the Covariance matrix or the variance Var(p,p1) for each par of products. The objective is to select the products what will maximize the expected demand Dem(p) at the same time, penalizes products with high variance. The uncertainty set will be a ellipsoid uncertainty. I would like to create the eelipsoid uncertainty using the uncertainty region like:Demand(p).level - sum[p1 , Var(p,p1) * …………There is a example in the book on page 341. but it’s not clear for me.  Could you help me to model the ellipsoid uncertainty using the uncertainty property? Thank you 

I am trying to implement the Rough Cut Capacity Planning for an school assignment. I currently have all constraints working except for the first constraint, since I do not know how I can loop over subset of time which is determined by two parameters release date(rj) and due date (dj). 

HiI am getting the following error while executing my code in AIMMS.ExcelSetActiveSheet(data.xlsx, Sheet1) unable to get a handle to the workbook: Could not open Excel.It would be grate if you can help me with this issue. 

Hi dear community, I tried to follow the tutorial https://how-to.aimms.com/Articles/85/85-using-axll-library.html#importing-data-from-excel-files to read in some data from excel sheet. I’ve installed AIMMSXLLibrary and put the data file directly in the library folder under my project (not sure it is required or not) as shown in the screenshot. Then I created the procedure called “ReadInDataFromExcel” in my project and used the code as shown in screenshot. But when I tried to run the procedure to test whether it can point to the .xlsx file or not, the AIMMS through out this error : The identifier "WorkBookName" has not been declared. I’m not sure what’s going on since I almost copy the code from the website. Could anyone please help? Thanks!

In WebUI in the Map widget I can change the outline of the label, but not the color of the label. Notice what my font looks like with the following css: Here’s the result: I recall having a similar issue with the labels on the Gantt chart, for which the solution was to use the selector .label. I have tried this with the map widget with no success. Can you please tell me what css I need to style this?

Hi, For some time now we have been struggling with communicating error, warning, and info messages to the end users.  We tried working with the dialogs (webui::requestPerformWebUIDialog) but found that unsatisfying because you have to be careful with the asynchronous workflow in the webui and you can not request a dialog when the user has a dialog open. So we tried to abuse the raise warning mechanism, only to discover the dark blue message displayed in developer mode (see screenshot) does not show in end-user mode.   My question is:  What's the best practice for communicating a simple message to the user? Like "Data saved”, "Order .. added, or "Invalid entry in field ...”. Thanks for your idea's!!   --- Ps. Perhaps I'm looking for something l

In our app we use excel upload and downloads such that users are able to change and distribute data more easily. So we have written procedures that write and read excel files for the data in the app. With the new widget actions, it seems most logical to also place these download and upload actions there. But there is still an option to download the data as a .csv file. As not to confuse any users which download they should use, I would like to disable the option of downloading as a .csv file for certain tables. Is there a way to disable this feature?

Hello, i am new to aimms and completed the beginners tutorial and tried to understand the machine planning example, but it was to complicated for me to understand all of it. I want to solve a scheduling problem but i have problems creating the model. Let me explain my situation: In the production there are build articles from different orders and they are transported inside the company within containers. The transport limitation is 8 containers an hour. I want to solve the problem and want the best order which is <= 8 containers an hour, if not possible, than the next following orders should be so small, that it will be compensated, if not possible, a gap with no production time should be inserted. It would be ideal, that the same article is produced in one step (e.g. Article 52107 has to be build for 3 different customer orders). After all, i want to visualize it. My first problem is, that i don’t know how to produce on order after another and make the timeline to

In this article you’ll find an overview of the HTTP Client Library itself, plus a guide to existing How-To tutorials for using the HTTP Client Library. These articles cover some possible use cases for HTTP requests to give you guidance and inspiration for your own applications.Basic overviewAIMMS provides multiple tools to connect your models with other applications.The HTTP Client Library provides built-in functionality to submit HTTP requests from AIMMS.HTTP requests are used to communicate directly with servers to call services or download online documents. Read more...

So I have seen (and used) things like .tag-ganttchart as well as .ganttchart, but what's the difference? Also sometimes .aimms-widget works and sometimes I need to use .theme-aimms. What's up with these? The only one I seem to understand is the .annotation-whatever_I_name_it class. But then I'm unsure if it needs to be code:.aimms-widget .tag-widgetname .annotation-whatever_I_name_it { fill: #FF0099} or code:.theme-aimms .widgetname .annotation-whatever_I_name_it { fill: #FF0099} or merely code:.annotation-whatever_I_name_it { fill: #FF0099} Everything works fine, but I feel like my CSS is