Optimization Tooling

This course focuses on developing your skills in recognizing and discussing decision support problems, understanding the key phases involved in handling them, and mastering AIMMS for effective management of these phases. It's a practical journey that begins with learning the phases of a decision support problem and culminates in using AIMMS for real-world applications. Gain essential problem-solving and decision-making skills in this course. 📑⏰Start Learning!  Any questions?Use this post to ask any question or curiosity! The community is here to help you. 😀

I am trying to understand if I am running into a bug or intended behavior in the coloring of the bar chart widget…. I have three sets:StoragePositions Days ProductsI have a parameter supply that is defined over these three setsFurthermore, I have a an element parameter that allows me to select a specific storage position in the GUI. If the supply is only provided for one product, the bars in the widget show different colors (which is NOT what I would expect, because I set  the product index in the grouped, or stacked, same behavior) part of the pivot in the widget settings: If there is one more other product during the time horizon with a non-zero supply value, the colors are indeed calculated per product instead of every bar having its own:  This is the coloring I would expect (and in the first image I would expect all of the 5 bars to be of the same color). Is there something I am missing in my own logic or is this a bug in the coloring within AIMMS? Attached the small demo project t

Our app has just been upgraded from AIMMS 4.91 to 4.96 and on startup of the project a pop up appears in the webUI: ‘page naviagtion is currently disabled’. This only happens on the pro cloud platform, not locally in developer mode. When using the navigation workflow there is message: ‘No control session connection, unable to run procedure: [object Object]. Does anyone recognize these messages and does know why these occured? 

Good day to you.I am modeling a situation in AIMMS and I have a situation but do not know how to handle it. The situation is that I am modeling variable 'P_Discharging(agg,t)' and I do not want it to discharge after the battery gets to <= 0.3501 and at the same time, variable 'P_Charging(agg,t)' and I do not want it to charge at >= 0.949. To achieve this, I have these figures: My main aim is to formulate a linear program. Just asking if what I have done is right or if I should model it using a 'Constraint' rather than ‘variable’. Moreso, I do not know how to model it into a 'Constraint'. Please, can you help me look into this? Thank you. Olusegun 

Dear Team, I am getting the following error while I am trying to run the cutting stock model in AIMMS. My input data size is large.   

Hello! I got an erorr message saying “Unable to map 'undefined' to an element within the range of set 'xxx' (in widget 'xxx)Setup as follows: Set A:= {‘Option 1’,Option 2’}. Element parameter eA with Range of the Set A. Create a widget selection box with content eA.Once I select ‘Option 1’ or ‘Option 2’ and I want to empty the selection box again (preferabele using the ‘cross’ but then I got the error message).  And using the delete button does not empty the element parameter eA. So how can I empty a selection box? (i know there if another topic but like I said the delete button does not work)I’m using aimms 4.91

I am facing the error in deployment of an AIMMSPACK  on AIMMS Web Pro as:Cannot verify project validity. Session 48f337e8-c168-451e-8a81-0fc460594b5f failed. Error message is: 'Error opening project/Starting up the Aimms project failed [error 3190].'. Check logs for details.Unable to understand why. Seeking help from fellow AIMMS users.

Hello - I'm creating a script to export a bunch of vars/params to Excel/CSV. It needs be pretty clean/standardized so it can be read into a UI.I tried:write AllVariables to file export_file;But the output was too messy.  - Is there a way to silence Basic/NonBasic? - My output is often Nodes x Time, which AIMMS seems to prefer as (n,t), but then it shows Time as columns instead of rows (which is SUPER ugly in the text file). So I have to duplicate everything as parameters with (t,n) for the export. Or am I wrong? So now I'm looking at using AXLL, but it's pretty tedious.This is what I'm currently doing:axll::CreateSheet("VarName1");axll::WriteTable(Var1, "A2:A5", "B1:AZ1", "", 1, 1);axll::CreateSheet("VarName2");axll::WriteTable(Var2, "A2:A5", "B1:AZ1", "", 1, 1);… ad nauseam There has to be a better way. Is there something like:for i in MySet do   axll::CreateSheet(FormatString(“%e”, i));   axll::WriteTable(i, “A2:A5”, “B1:AZ1”, "”, 1, 1);endfor; I want to print one variable per tab in

Does AIMMS store the information after an user triggers multiple upon change procedures.For example, 2 parameters are in a UI table and an user uses block editing to change both parameter , both wiht their own upon change procedure.Can you know as a developer during the first one that called that also a second will be called later.(i know the order depends on the model tree)

Hi All,I hope you are doing well! I have a question:I am programming a model with 3 objective functions. The goal is to find the best locations for production.I have diffrect sources, one destination and 4 products.All the objective functions are linear and I used GMP::Column::SetAsMultiObjective to solve them similar. The first function minimizes the costs (price * X(decision variable) + transportation cost * X)The second one minimizes the produced CO2 (CO2 in production * X + CO2 during transport * X)In the last one I want to maximize the social benefit, therefore I wanted to use a binary variable, so if X at a source location is > 0 the binary Variable Y should be 1 (0 otherwise).so the objctive function should be: (Number of created Jobs + other social aspects) * Y This is what I got so far: When I add Y to v_objectiveFunktionSocial the error appears that multi objectives are only for linear models.Is there a way to work with a binary variable here? Or mybe someone has an idea h

In the winUI of AIMMS, there is the DialogGetPassword function that will create a dialog window with a masked input that can be used to retrieve passwords. Is there any way I can achieve the same in the WebUI at the moment? If not directly supported by AIMMS, I could think of a bit of Javascript that could find the right input tag and modify the type from text to password. Is this possible within the webui? To add som custom javascript that is running on the page?

Hi All,can someone explain how to enter this as a constraint in AIMMS:(“für alle” means for all)This is what I did:I always get an error notification :(Thanks in advance! Best,Eddy

Hi, Playing around a bit with AIMMS again and was looking first at using a workflow, but the problem I think for me is that changes I make in a later step could invalidate an earlier step again. For example, one step in the workflow would be to request the user to upload 3 files, while next steps in the flow would be fixing some of the items that were just imported. However, I don’t think I can make it three separate steps in a workflow because changing something that was read in from the 3rd file could invalidate something from the first file. So based on earlier conversations, I was looking at using the list widget in a side panel because this can easily give me the non-linear behavior. For each of the three input files, I would have one line in the list widget and I can use green checkmarks / red crosses / yellow warnings to indicate which blocks need to be investigated. Is this indeed a good approach for these kind of things?  With regards to the side panel, when adding the list wi

While writing the suffices ProgramStatus and SolverStatus from a MathematicalProgram identifier to an Excel file using DEX I get numeric values rather than the lables indicated in this table:https://documentation.aimms.com/language-reference/optimization-modeling-components/solving-mathematical-programs/suffices-and-callbacks.html#table-mp-status Is there any way to write these labels rather than the corresponding numeric values?Otherwise, where could I find the corresponding mapping between the numeric values and the labels (status) referred in the previous table?

Is it possible to write ad hoc text to an Excel file using DEX? How? Otherwise, is it possible to write it using AXLL? How? Thank you

In an effort to improve the Tabular Data Manipulation experience on WebUI, we added and released "Excel Upload/Download Support" Table feature with 4.86 version. Using its Download Excel and Upload Excel capabilities, this functionality provides a means of manipulating Table data.The user can choose to download the entire table's contents into an excel file, edit the data, and then upload the updated data back to the WebUI. We firmly feel that the user benefits when the Table has a sizable amount of data and the user is able to edit the data utilising Excel's features. I’m looking for your feedback on this feature, specifically:Any suggestions on improvements on Excel Upload & Download feature on Tables Do you still need "Download CSV" feature, and what are the use cases? (Can they use the Downloaded Excel data for such actions?) Please tell us in the comments section below. Thanks,Team WebUI

Dear all,I have a problem to open a project that is located in OneDrive folder. But, when I move the project in Google Drive folder, the project is correctly loaded.Is there any setting in AIMMS of OneDrive to solve this issue?Thank you very much.

Did you know that every AIMMS Cloud account is by default equipped with an Azure Data Lake Storage Gen2 (ADLS). You can use this storage account to store all types of files that you want to integrate with your AIMMS application. You can also use it to store files generated based on the output of your optimizations, as to make them available to an external source.We’ve posted a how-to about this new DataLake toolkit now in place!The Data Exchange Library offers functions to easily interact with the ADLS.This toolkit offers you the possibility to easily create a SAS token which is needed for authentication if you want to access the ADLS from an external source. It also allows you to fetch and manage the currently known file systems (‘containers’) on the ADLS and the paths (folders) and files in it.Come and see! 😀

Hello all, I am working to use the OAuth2 flow for the DEX library with a Google service account. Rather than allowing the user to make calls, we would like an OnPrem server to make the call to the Google API. However, Google does not provide a client secret for the Client Credentials flow. Rather, the provide a private key id, private key secret, and client ID (but only for certain scopes). How do I use this in the DEX library to communicate in this way? I don’t see anything that allows this behavior. -Matt

Hi All! I have read the documentations but I haven’t find the detailed answer I would need. How can I access and restore AIMMS Pro backup? Is there any special process for it in AIMMS Pro? Thank you in advance!

 Hello,I would like to know if it is possible to start reading files from a certain line when importing an .xlsx file using the dex library. And how could this be done?I have a file that contains four header lines and I would like to perform the import ignoring those lines.Thanks 

 The binds-existing attribute can be used in conjunction with the binds-to attribute to indicate that, when reading a data file, no new set elements will be created, allowing for a filtering mechanism where a data file can only be partially read for the nodes that correspond to existing set elements in the model.I have a predefined set named t with valued {1,2,3,4}.I want to read an Excel file which contains a column named “time” having values (e.g., 0, 5, 6) not included in the previous set, which I do not want to add to set t.I am specifying the binds-existing attribute in the DEX mapping as follows:<ColumnMapping name=”time" binds-existing="t" binds-to="t" />I have not changed the skip-non-existing attribute, so I was expecting that binds-existing attribute would not add the referred values (0, 5, 6) into the predefined set t. However, it still does.What am I doing wrong? Did I correctly specify the binds-existing attribute?Thank you very much PS: There are almost no specific

Model descriptionWe have a non-linear mathematical model with the following set, variables, and parameters: Set t in [1,N_T]     Variables x_t y   Parameters A B C_t  And the following objective function:min{sum((x_t-A)/A) for all t}Subject to:x_t = x_{t-1} + B(Ay - x_{t-1}y - C_{t-1})x_t >= 01<= y <= 2499999With the initial value of the variable x_t being:x_1 = 19,500The values of the set are:t = [1 2 3 4 5 6 7 8 9 10]The values of the parameters are:A = 21,500B = 0.00095C_t = [50,000 50,240 50,300 51,000 51,040 50,700 50,800 50,200 49,000 48,700]SolvingThe non-linearity in the problem lies in the following product in the constraint:x_{t-1}yWe have implemented the model in AIMMS and tried the Outer Approximation algorithm for this problem, but get the following error message:The generated mathematical program “OA_NLP” has type “QCP” which cannot be changed into “RMINLP”.What might be causing this message? Also, does anyone have suggesti

Given the example of the data I would like to bind each sales volume to a period and sales channel to fill the following parameters . P_MinVolumeSalesChannel(i_Product,i_DemandTerminal,i_Period,iSalesChannel). P_MaxVolumeSalesChannel(i_Product,i_DemandTerminal,i_Period,iSalesChannel).  I know that I could use name-binds-to =”i_Period” and the name-regex-prefix, but could I use name-binds-to again for “i_SalesChannel”?