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Dear All,I have a question on how to limit the range of an index and since I’m new to Aimms I can’t find a proper solution. I just want to limit certain indices to a certain range for a specific constraint.First example (Constraint):Index Domain:tDefinition: e(t) <= e(t-1) |t<Tmax |t>TminError Message:In an inclusion only the middle term is allowed to contain variables, however in the inclusion e(t) <= e(t-1) $ t < Tmax $ t the left term contains variables. Second Example (Constraint):Index Domain: (i,j,k,t)Definition: r(i,j,k,t) <= o(i,k-1,t-1)*RM(i,j) |k>1|t>1Error Message: The operators <= and > should to be the same for numerical inclusion (or use parenthesis). As I’m new to aimms I dont seem to understand the principles properly. May someone point me to the right way to do this?Thank you very much in advance!Best RegardsJonas  

I was wondering if it is possible to change the shape of the node on the map from a circle to something different, e.g. a square or triangle? I am already using color coding to indicate allocation of store locations to warehouses, the shape is intended to differentiate between 3 different types of stores.Using of icons or alterntative stroke colors doesn't really work, because the nodes need to be quite small. But I am also interested in any other suggestions to make it work.Thanks!

Hello everyone, Since I’m starting on AIMMS, I have two little questions : One of my index, called t, goes from 1 to 15. But for one of my constraint, I need that it goes from 1 to 14. How can I express that on AIMMS ?  In order to get the bound after the addition of cutting planes by the solver, my teacher told us that we can limit the number of branch-and-bound nodes to 1 by going to menu solver options. The problem is that cannot find this menu on AIMMSCould you help me ? 

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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.  

Hi, I am going through AIMMS FOUNDATION COURSE, where trainer asked to declare Set Index as 1, 12 when i am doing that getting error that “The symbol '1' is not expected but a symbol like 'identifier' is expected.” 

Hi all,my question relates to the font size of axis labels when enlarging the respective widget to full-screen mode. The font size is fine on the normal page when the widget is its standard size. However, when zooming the widget, the font size stays the same, making it very hard to read.Especially when making screenshots of the charts to use in e.g. business presentations, it would help if we can adjust the label size when enlarging a widget.Any suggestions as to how I can do this?Thanks in advance 

Dear Community; We are working with some MILP problems where we need to identify the ShadowPrice of some constraints. These constraints are made up of both binary and continuous variables. As the duality is not well defined for MILP problems, one method to find the ShadowPrice is to run a LP fixed model right after MILP solution. I see that AIMMS provide ShadowPrice by default for MILP problem when the variable property “ShadowPrice” is defined. We need to know how AIMMS calculate ShadowPrices for MILP problem? Does AIMMS use a method similar to post MILP fixed LP execution? A quick additional question: Is it possible to identify and set all Bianry and Integer as “nonvar” (i.e. if var is Binary then var.nonvar := 1) -- the idea here is to manually prepare a fixed LP? I do not see how AIMMS support fixed LP preparation and its execution. Thank you;Amrit Gill

HelloI have created another model for practice on AIMMS for inventory optimization. There are no errors during compiling however I am getting the attached error while running the procedure in the Main Execution part. The model and the error have been attached as a zipped file for reference. Thank you for all the help! 

Dear All, My name is Mohamad Khaled and for my university research project I am using AIMMS to model a 3-echelon Pharmaceutical Supply Chain model. The current model I’m trying to define and solve is a simple one compared to some of the models I have seen here. I have two issues with my current model: The first issue is that the pharmaceutical products (AKA medication) has an uncertain demand which I am not able to properly define in the project despite indicating the index domain, using the uncertain option in the property setting and defining the box function with an upper and a lower value in the region area. (I attached a screenshot of the demand parameter with the descriptions and region and another screenshot of the current “nominal” data of the demand)  The second issue is the wastage/expiration of the medication. I have defined a shelf-life variable and respective constraint, however, I couldn’t get the shelf-life variable to be used in the wastage constraint as the following w

Hello,I am solving small MINLP problem using BARON solver to find the ‘optimal’ solution. But for such a small system, 8 hours passed and I have not got the solution yet. My question is: why this solver cannot find the solution after such a long time? Is this because of the way I implemented the model? (If so, I am attaching my code here to let you know how I did it). I would appreciate it if you could help me solve this problem. Thank you!Regards

Hi, I would like to know how I can give an initial integer solution to a MIP solved with CPLEX. I found this link on the topic but I’m not convinced about the option it suggests for CPLEX in particular “Advanced basis” sounds like a setting to warm start an LP, not a MIP. I’m also not sure how to actually give my heuristic solution to CPLEX after that.https://how-to.aimms.com/Articles/108/108-kb11-mip-initial-solution.html.I also found this related question, but the link in the selected answer seems to be broken: https://community.aimms.com/developers-math-or-programming-39/how-to-start-solving-with-an-initial-solution-466.Thanks

I have created a model on AIMMS for production. There are no errors but still we are not getting any result. I tried multiple modifications, but I am stuck. I am attaching the model for reference. The formulas have not been used anywhere else except for the attached files.

I would like to freeze the left most column in one of my tables. This column contains an identifier with no values in other columns. Is this somehow possible via CSS or some AIMMS logic I am not aware of?

I run Power System Optimizer (PSO) developed on AIMMS. The current version of AIMMS we have is 4.30.5.814 on the windows server. The software ran with no issues till last week. However, after probably the server update, AIMMS crashes each time I read input files and throws the following error: the thread tried to read from the virtual address for which it does not have the appropriate access. I am not sure what the issue is as the input folder has complete privileges for read/write.

Dear Community, I plan to work from the Python workbench to call AIMMS to execute the optimization for my research project. I have some questions about linking AIMMS to Python: 1) How do I execute the AIMMS file by calling it from Python? 2) Will the results be written back to Python? Or, how can I export the results to the Python workbench? Thanks in advance, I look forward to executing my research with AIMMS... Best regards,

Hi there,I’m having an issue with AIMMS which is preventing the advanced text editor from working.When I launch AIMMS I get a Windows pop-up asking to install the Microsoft .NET framework 3.5. Then in AIMMS I get the error:Unable to locate the SyntaxEditor .NET assembly, falling back to ordinary editor.However, my machine is already operating the .NET framework 4. I’m using a work machine so am unable to roll back/install the older framework.I’m running Aimms-4.76.1.1-x64-VS2017.Has anyone had this issue?Any ideas on how I might be able to get it working?Thanks for your help! 

In our team, we are working on a linear energy system model which is expanding every day. We use the LP Gurobi solver with multi processing. Currently, it has 250M non-zeros (after presolve) and we think it will grow to more than a billion. If the computational capacity (let's say several hundreds GB of RAM) is present, is there any limitation on the problem size on AIMMS side?In particular I am interest in any limitation on number of variables, constraints, or non-zeros? or any limitation on the capacity of committed RAM or number of CPU cores for parallel computing? 

It is probably very simple, but i cannot figure it out and i need to get it done asap. Really appreciate any help!I have created a project that runs and gives me solutions. Now, i need to create another version of my model with major changes, but to make it faster i would like to “save as” the entire current project and then start making my changes. the “save as” menu only makes another copy of .ams file within the current project, but doesn't make an entire new project. i also tried to export a section, but the “Export” menu is not active.could anyone advise on how?

I created a very simple pie chart using a parameter with one index with 2 elements, named “Actual and “Penalty”.I was expected that the pie chart showed me the names “actual” and “penalty” inside the wedges, like shown in the article: https://documentation.aimms.com/webui/pie-chart-widget.html I also tried an elementtextidentifier to the set I use, although I would expect this does not make sense since the element are already named.I can’t find anything related in the pie diagram options or do I miss something?

Hello, We load back job data (optimization infos) from AIMMS PRO to the user session. I would like to display the status of the job. I only found the status code parameter but nothing about what is the status code list and meaning. Can somebody help me with that?Thanks, Zsófi

Is it possible to initialize local parameters, which have the property RetainsValue set? The first time, that the procedure/function is called, I would like the parameter to be initialized by a certain value. Afterwards, when the procedure/function is called again, I would like the parameter to keep the value from the previous procedure call.If I set Initial data for the parameter, the behaviour of RetainsValue is lost and the parameters is initialized with that value in every call to the procedure.

I find that unit conventions are an effective way to display data in different units. E.g. capacity in #items/day, with accompanying cost €/day, are relevant numbers for location specific KPIs. On a higher level, we can change convention to e.g. #mio Items/year, or mio€/year.However, I don't want to apply the selected convention on all my model identifiers. E.g expressing cost per item as €/item, and not as mio€/mio Item when the yearly convention would be selected.Is there a way to override the conventions in model identifiers, and thus explicitly define what uom to always display?Thanks!

Hi All,For a project we are implementing a user is making changes to a relatively large table. The user has the possibility to store these changes in a database.However, when a user closes his/her browser after having made these changes and forgets to store the changes in the database the changes have to be made all over again. Is there a way to raise a warning when closing the browser? In this case that would refer to a user that has made changes, but has not stored them in the database.I know using a uponleave procedure works when navigating to a different page, however when closing a tab no warning is raised using such a uponleave procedure. Furthermore, I have seen multiple sites raising a warning when closing the tab, so curious to see if this is possible to do in the AIMMS WebUI as well! 

Hi community,I have a three-dimensional parameter I would like to import. I know how to import one- and two-dimensional parameters, but do not know how to do this one. The data is stored in excel (I have attachted a snapshot as illustration of the structure of the data), I can extract (with some formulas in excel) the range (AM3:AO32) from which i would like to import the data. I also know the number of products (6), number of locations (5) and number of time periods (3). Can someone help me out with this?