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Hi Community, i have to build a robust optimization model for my masterthesis at the Technical University in Braunschweig. Therefore i choose the Minimax-Regret Function! These approach deals with different scenarios k. I need to implement this function in an existing basic model, which is a single factory location problem. The basic model calculates the minimal sum of all deviations "d" from target values (so it is a Goal Programming approach) and based on these deviations the output of the model is one compromise-optimal location solution (the basic model is based on one scenario). So first i implement a new index k for the scenarios to dealwith more than one scenario. How to deal with a minimax-obejctive function in AIMMS is already explained very well in one of the AIMMS Modeling Guides ([url=https://download.aimms.com/aimms/download/manuals/AIMMS3OM_LinearProgrammingTricks.pdf]https://download.aimms.com/aimms/download/manuals/AIMMS3OM_LinearProgrammingTricks.pdf[/url]). But i ha

Is it possible to disconnect automatically users in AIMMS PRO after being inactive after some minutes?

Dear, In the attached model, you should only run the procedure ReadFromExcel. This should load all the relevant sets and parameters. When I try to solve this model, I encounter different memory errors. I either see: [list] [*]Memory allocation error [*]Memory allocation error: while assigning "xxx" bytes [/list] Are there any steps that I could take with regards to the index domain of some parameters, constraints or variables, such that this model becomes solvable? I think there are no other errors in my model, but would also like to double check this. Kind regards, Koen

Dear Ladies and Gentleman, I use the solver Baron for a NLP and solve several problems with an if function in the Main Execution. After a specific time limit is exceeded, I want to save the Upper and Lower Bounds in a file or even better in a Parameter. Is this possible? Best regards, Jacqueline Wand

Dear all, I have a few questions about my model, which I hope the AIMMS community can answer. Please bear with me, as I should be drawing to the conclusion of my thesis (when this model works). [i]Sum and indices[/i] In the accompanied model, I am trying to add several constraints. However, when setting these constraints I often encounter errors like "the index (p) does not denote a subset of the domain of set "FactoryLines"" for instance. I often find that I make mistakes with the indices in the constraint itself and within the constraint definition. I have tried looking at the guides online, but with no effect. Could anyone explain to me (preferably in layman's terms) how the indices in constraints work as well as indices within a sum argument? I am encountering similar problems with the parameters "IncomingStock" and "OutgoingStock" [i]Stock balancing[/i] One of the decision variables, StockAtWarehouse is made from the following definition: StockAtWarehouse(p,w,t-1) + sum(p,

Is it possible to select not only one but more tasks on the WEBUI Gantt-chart? I couldn't find any description about that. Does somebody have any infos about that? Thanks, Zsófi

Dear staff, I need your help with an objective function where I have the product of two variables. I have the following variables and parameters: y(i,j,c,a) binary variable x(a) continuous variable P(c) parameter How can I linearise the following objective function: MIN: sum((i,j,c,a), P(c) * y(i,j,c,a) - P(c) * y(i,j,c,a) * x(a)) Thank you

Hi, The CSV Export DLL does seem to export 0-dim identifiers. Therefore I would like to use put. However I can't figure out how to obtain the value of that 0-dim variable. I have the next snippet of code, which works fine, but the value of the variable is still missing. [code]for (IndexVariables) do if (IdentifierDimension(IndexVariables)) then !do something else else csv_alt_name := FolderName + IndexVariables + ".csv"; put csv_alt; put IndexVariables + "\n"; put name_of_some_variable; putclose; endif; endfor; [/code] The line "put name_of_some_variable;" prints the value of a variable. But it should of course print the value referred to by IndexVariables. How to do that?

The WinUI has a super obvious tab for the Legend of a linechart. But there seems to be NO way whatsoever to display the legend (or anything that will work as a legend) on a WebUI linechart. I even tried the (seemingly obvious) solution of using a legend widget. If this will work, I can't figure out how. Is there a way to show the legend? And if you don't have on yet, is there a workaround and do you have it in the plans in the future?

Dear Staff, I need help writing the following constraint using the AIMMS language. I have two indexes: c a Where "a" indicates years. I have a variable y(c,a) I would like to define a summation over "c" and over "a" as less than or equal to a value. But the summation over "a" should be done only from the first year until the current year. I am trying this formulation but something is wrong with it: sum((c, a1|(a1="A01") and (a1=ord(a))), y(c,a1)) <= Value Can you please help me writing this correctly using the AIMMS syntax? Thank you,

I tried to set my Gantt-chart to readonly, such that users would not be able to move any tasks on the Gantt-chart. Unfortunately I cannot find neither this option in WebUI nor in any AIMMS Manual. Could you help me to set it up? Thanks !

Hi, is there a similar code that I can use if a project has set the option Data Management style to Disk files and folders? The below code was valid for projects using option Single Data Manager file. The code was available from https://techblog.aimms.com/2012/06/05/save-a-case-from-aimms-procedure/ (note this is blog is now not available) ************ !First try to find a case with the name indicated by CaseName. If AIMMS !can find this, it will store a reference to this case in the element !parameter CaseReference if ( not CaseFind( CaseName, CaseReference ) ) then !If no case with the name indicated by CaseName could be found, then !we try to create a case with this name. After creating the case, AIMMS !will store a reference in the CaseReference element parameter to the !newly created case if ( not CaseCreate( CaseName, CaseReference ) ) then !If there was an error while creating the case, notify the developer !by raising an error. If the raised error is not cau

Hi, When I run AIMMS, I’ve got this result in the progress window as shown in the picture attached, I wish to know what they are mean and how they work. Can anyone explain it to me? 1. infeasible 2. integer infeasible 3. intermediate infeasible 4. terminated by the solver 5. solution does not exist 6. solver not called 7. left 8. nodes 9. thread 10. nonzeroes 11. variables Thank you in advance.[img]https://uploads-eu-west-1.insided.com/aimms-en/attachment/84219ee6-380c-4d4d-b0df-5d3bf0fc1883.png[/img]

Hi, I have an integer set, a parameter with filenames, and a parameters with Aimms'standard date/time. How do I select the newest file, or how to sort a parameter and select the first, or how to select the smallest, largest? Thanks!

I was fixing to put some page actions on my app and holy cow! There's no more little rocketship! Where did it move to? Thanks!

So I have seen (and used) things like [i].tag-ganttchart[/i] as well as [i].ganttchart[/i], but what's the difference? Also sometimes[i] .aimms-widget[/i] works and sometimes I need to use [i].theme-aimms[/i]. What's up with these? The only one I seem to understand is the[i] .annotation-whatever_I_name_it[/i] class. But then I'm unsure if it needs to be [code].aimms-widget .tag-widgetname .annotation-whatever_I_name_it { fill: #FF0099 } [/code] or [code].theme-aimms .widgetname .annotation-whatever_I_name_it { fill: #FF0099 } [/code] or merely [code].annotation-whatever_I_name_it { fill: #FF0099 } [/code] Everything works fine, but I feel like my CSS is just a scrambled mess with all these different bits. I don't want to be THAT developer. Please help. Thanks! ~Bon

Hi, There are some changes I did on the setting before I run my MIP project in AIMMS. I wish to know what they mean and how they work. Can anyone explain it to me? 1. I change the ‘aggregrator’ to 0. 2. I change the ‘global thread limit’ to 1. Thank you in advance.

Hi, How to control/change the gap according to what we want? For example, I want to set the gap for 0.5% instead of 0.0%. Where should I insert the value? And how should I write the value in the AIMMS? Is it 5% or 0.5 or 0.05. Best regards, Zahidah Zaulir

My WebUI app is looking mighty spiffy. However, whenever AIMMS takes an extra second or two, I see this blue busy spinner. Alas, that is not in my color scheme. How can I change either the color of the spinner or the .gif itself so that the spinner matches my look and feel? Thanks!

I'm liking the group widget in WebUI, but I'd sure like to put more than a few buttons across it. I want to have a row of buttons all the way across the top of the page, and the only way I can get the buttons to not be 2 columns wide each is to use a group. But the group cuts off any buttons that exceed about 4 columns wide! How can I get either more buttons in a group all in a row or smaller buttons that I can place individually? Thanks!

The only resource I can find that explains how to do a form is [url=https://techblog.aimms.com/2016/03/10/using-aimms-webui-forms-to-create-and-edit-data/]this post from March of 2016[/url]. It seems the newest WebUI doesn't quite work this way. Is there a link to the actual way the forms work? And can you link that in that blog post so that others can more easily get to it? Thanks!

[url=https://community.aimms.com/topic/show?tid=238&fid=44]Over here[/url] y'all explained how to change the css on dialog page buttons. But that doesn't trickle down to my confirmation/warning buttons. How can I change those? Thanks!

Hi, Is it possible to stop a cplex milp solver, save to disk and resume later? How to do that? Thanks! EDIT: Does this work... [list=1] [*]Start cplex milp solver and wait for incumbent solution [*]Save a case file with an incumbent solution to a case file. [*]Restart AIMMS, open model and load case file. [*]Set Advanced start -> Use advanced basis. [*]Start cplex milp solver again. [/list] Is there another method? Is this similar to just letting the solver continue? Is it possible to save and load the tree? Is that required? Thanks.

Hi, Is it possible for a callback procedure to save the newest incumbent solution to a case file. Is an example available? Edit: I already installed a callback procedure (SetCallbackNewIncumbent). How can I access the new incumbent solution from that procedure? And do I need to send the new incumbent solution to the model first, after which I can send it to a case file, or can I send it to a case file directly? Thanks! Best, WM

We have a stock that can be negative as well as positive. If it is positive then there are inventory costs and if it is negative then there are backordering costs. We wanted to model this in aimms with different methods. On the one hand we got the error that it was not linear, If we wanted to only have the stock if it is positive and otherwise return the value 0. If we tried to use other methods, such as a binary value that would return the value 0 if the stock was smaller than 0 and 1 if the stock was bigger than 0 we got the following error "The mathematical program "CostMinimization" is not linear, look for bracketed numbers in the constraint listing, for example in the constraint Inventory_definition(4,12)." How can we best model this situation, so that it is still a linear model?