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Hi,I think it would be helpful to provide a little bit of background regarding my problem first. I’m currently working on a project where a given set of volunteers should be assigned to a given set of people in need. So basically a simple transport problem, where the demand of all people in need is 1 and the supply of all volunteers is 1. The model in AIMMS always expects a balanced problem. So in case of a surplus on either side, dummy persons will balance the problem. The data for a set containing all persons gets read from a file like this. The first half are the people in need and the second half are volunteers. The last X amount of people in need would be dummies in case of a surplus on the volunteer side. The last X amount of volunteers would  be dummies in case of a surplus on the other side. The example below shows a data set that was already balanced, so without any dummies. Based on the parameters NumberInNeed and NumberVolunteers the AllNodes Set containing all persons is de

On WinUI the Network Object enables a developer to modify the color of an Arc based on Arc Origin etc.  Is this feasible on the WebUI as well on Aimms, and specifically on aimms 4.70 

Hi, In my model I want to minimize the (maximum_t of a function) - (minimum_t of that function) and I have solved this issue by setting: k >= function for all tp <= function for all tand adding (k-p) to the objective of my model. When I do this for one variable, it works, but: when I do this twice (for different variables and hence adding two variables to the objective) it does not work. This while these variables are not connected. Can anybody maybe help me with this? Thank you in advance!

Hi all, I am new to AIMMS and I was wondering if someone could help me with my model.   I would like to maximize profit, fulfill as much demand as possible + keeping a safety stock. Besides reorder quantity is restricted by a maximum order quantity (see Sets, Parameters, Variables and Constraints attached).   I linearized min(Demand, E).  E = demand fulfilled  However, when I introduce the maximum order quantity constraints the model becomes infeasible.   Besides, the listing file results in the following messages: CPLEX 12.10 constructed the following irreducible infeasibility set (IIS). The IIS consists of 3 constraints and 4 variables. Stock_definition(B,NL19,p-1) .. [ 9 | 31 | IIS ]     - 1 * X(B,NL19,p-1) + 1 * Stock(B,NL19,p-1) = -120320 ; (lhs=0) **** Stock_definition(B,NL33,p-1) .. [ 9 | 43 | IIS ]     - 1 * X(B,NL33,p-1) + 1 * Stock(B,NL33,p-1) = -428130 ; (lhs=0) **** OQ_B(p-1) .. [ 9 | 152 | IIS ]     + 1 * X(B,GB13,p-1) + 1 * X(B,NL19,p-1) + 1 * X(B,NL30,p

Hi there,I am trying to add stochasticity to a deterministic MIP model and I am receiving the following message:The empty row em.Stochastic([M,L,L,L],(B),(B)) .. 0 <= -39688691.0796 is infeasible, as tolerance the option "Bound_Tolerance" is used with value 1e-08.This constraint is:index= (i,j) - at the error message (B) is i and (B) is j;definition sum((k,t), Flow(k,i ,j ,t)) <= sum((e,t),EmissionProfile(e,t))EmissionProfile is the parameter with the scneario tree and Flow is the stochastic variable. Worth to mention the deterministic model is running with no issues I appreciate any light on this topic or how to debug it.Thanks and best regards,Denis

Hello, everyone.I have been working to develop a WinUI for an AIMMS project. The UI development is almost over and I am trying to create an executable file (or anything equivalent in AIMMS) for the project so that any user can only access the user interface (without seeing the source code) and run the project. Could anyone please guide me to any resources that explains how to create such executable files?  Thanks.

Hello,I am working with the MINLP problem which is solved by AOA in AIMMS. But I get different results whenever I run the code. Could you please tell me why this is happening? I can share my code with you if you need. Please tell me how to upload my code here?Regards

Hi there, for a project within my studies I would like to do a numeric analysis of several Iterations of randomly generated input data of the customers demand. Can anyone support me by implementing and running the iterations? Many thanks in advance!

Hello,I would like to know if there are any  theorical references of why the default value of the bad scaling threshold is  “1000”, or this default is due to the many yeras of experience of the Aimms developers? 

Hi. I have a parameter with index domain (scenario, year). I want to have a plot of parameter (scenario, year) vs year which looks something like in the image attached. In the image, for example, the number of scenarios is two. However, in my project, the number of scenarios changes with user input data.  Could anyone please guide me to any resource (example project) in which such type of plots are generated or could give any suggestions how do I proceed to create such plots? Thanks. 

Hello guys,   currently im doing a Project at my University. I have to do a Simulation Pretty simular to the tutorial for begginers.  But i have some more constraits which i have to imply but have no clue how to.code theese. In General: I have to get my products to the different customers. but i just have one “car” with a set storage. the case is, that the car definetly Needs to drive sometimes back to the warehouse, but i want to optimize the Situation.  for example: i can fit product a for customer a in the car. and the half of product b for customer b. so i want to know whether it is more worth driving back and then Picking up the whole product for customer b. or is it more worth to immediately drive to customer b and in the 2nd route i allready can pick up e.g. product c for customer c.  In Addition to this: i also want to imply, that there is a amount of time needed to put the products in and out of the Vehicle.  My native language is not english, but i hope you could understa

Hi, In vs 4.74 I get an errormessage, which did not appear in vs. 4.69.: "A function call in the initial data of a set is not allowed. Either use a definition or assign the set in a procedure.", I see that when opening the declaration the set property is "initial data”, and I used the function elementrange for definition. However, I do not see an option to change "initial data” into "definition”. How can I repair this?  

Hello, I hope there is a solution for my problem  I was working on a project for my class on AIMMS software (license provided by the university) online and when I save the file, I don’t know how I save it but it got extension .aimmspack. Now my instructor is not able to review my project since the version seems to not be compatible with his… He asked me to convert the file to .ams but I have no idea how to do it. I don’t have the software in my computer and don’t know anybody who has that version to convert it and pass it over to me…. Please any recommendations? Or can someone help me?   

Can I create a WebUI with my free academic license?

When I want to use the modulo function in my linear model, I get the following error: “Constraint programming constraints cannot be used in combination with real valued variables, only with integer valued variables, element valued variables and activities.”. In my constraint I calculate the modulo of (x_{zht}*(t-1), Z) where Z is a parameter and I have used the function Ord to calculate the first part of the modulo, so x_{zht}*(Ord(t)-1). Also, I have tried making the indices a subset of Integers and label it as numeric, but then the model does not give any solution anymore (even when I turn the modulo constraint off). How can I make the constraints containing the modulo function in my linear model work?

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!

Hi. I am trying to plot a pie chart in a user interface. The colors repeat for different pie sections as can be seen in the attached image.  How do I set different colors for different pie sections. Thanks. 

Hi, i want to visualize the frequency of postcodes from a table with a barchart,  but I didnt have any ideas how to do this. Can somebody help? Thanks    

What are some best practices to develop WebUI’s to consider a user who has their screen set to say 125% magnification in Windows? Am I stuck with just changing my screen magnification to see the results?

Dear All, I did a save as to a new case and run the model again. However, I cannot open the new case and the dialog box said that “is not an AIMMS case file” as shown in following figure. Is there a way to fix this? Many thanks.

Dear all, I would really like to seek for your kind help regarding an if-then constraint. I found in the community a similar topic but my condition is a bit different from that, therefore I want to show my case and ask for your tips again.   Specifically, I have the following variables: A: decision variable B: variable Q: variable   And I want to achieve the following: 1)if A-B>=0, then Q=A-B 2)if A-B<0, then Q=0   I would like to ask if it is possible to consrtuct a linear formulation for this if-then logic to be realised.   Many thanks in advance! Xubo  

Dear all, In my model, I work with multiple factories. Each factory has a minimum lotsize requirement, meaning that IF a product run is initiated, it must be at least xxx big. I tried to put it in as follows: I have a parameter MinimumSKULotsize(f), which specifies the minimum lotsize per factory; I have a binary variable ProductInFactory(f,p,t), where 1 indicates a production run of that product at that factory in that time unit, and 0 does not. I have a variable ProductionAllocation(p,f,t) which indicates how much of each product is allocated to which factory at which time unit. I tried to add the constraints: SKULotsizeConstraint0 with index (f,p,t) | ProductInFactory(f,p,t) = 0 and definition ProductionAllocation(f,p,t) = 0 SKULotsizeConstraint1 with index (f,p,t) | ProductInFactory(f,p,t) = 1 and definition ProductionAllocation(f,p,t) >= MinSKULotsize(f) However, I am getting the warning: Warning: The index domain contains the variable "ProductInFactory". The use

Hi everyone, Today I was running my energy model and I faced this weird infeasibility in the listing file:  balance_activities(Houses - Residential Terrace,2050) .. + 1 * tech_use(Res03_01,2050) + 1 * tech_use(Res03_02,2050) + 1 * tech_use(Res03_03,2050) + 1 * tech_use(Res03_04,2050) + 1 * tech_use(Res03_05,2050) >= 4060 ; **** name lower upper tech_use(Res03_01,2050) 0 0 tech_use(Res03_02,2050) 0 0 tech_use(Res03_03,2050) 0 0 tech_use(Res03_04,2050) 0 0 tech_use(Res03_05,2050) 0 4060.000 It seems the upper bound of tech_use(Res03_05,2050) is respecting the mentioned constraint as 4060.000 is larger than 4060. Do you have any idea why AIMMS arises this ifeasibility? Thank you in advance.

Hello together, I have declared a parameter as an Min-Operator, which have to indicate the minimal objective function value for each k across all j.  Background: In each k at least one j is infeasible (objective function value = “na”) as certain restrictions are violated. As a result, the problem occurs that the Min-Operator outputs "na" as the minimum value for each k. The Min-Operator’s definition is as follows:       Index domain: k           min(j,Parameter(j,k)) Does anybody now how to exclude “na” in the Min-Operator’s definition? Thank you in advance! Best regards David

The column, by which we want to sort, contains an element parameter whose range is a calendar. If I sort the table by the column, it sorts as if its elements were strings, not dates.