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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

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,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

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

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.

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 

Hello all together,Unfortunately I am a complete AIMMS beginner and can't get any further on my own.Can someone please help me to build this model (I have only the Academic License):Four products can be produced in a total of 10 locations (but not every product can be produced in every location).All products should then be transported to a fixed location.3 objective functions are to be considered simultaneously with different weights (minimize production costs, minimize CO2 emissions during production, maximize social impact due to production at each location).A few constraints should be taken into account, e.g. if 2 products come from the same location, the transport costs should be reduced, etc. This model should answer the question: how much of which product should be produced in which location? Thanks for your help!

 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”?

I want to map data from an Excel file using DEX ExcelSheetMapping to a parameter named “Capacity”.However, I cannot get that null (“0”) values are read into the parameter “Capacity”.I have a constraint that imposes an upper limit over a variable named Stock, as follows:Stock <= CapacityI need to read null (“0”) values to impose that the variable Stock is null.How can I do it?Thank you PS: I omit indexes for the sake of simplicity

Hi, when I solve an optimization problem (which is convex), though there should be only one optimum solution theoretically, I can get nearly the same objective value but totally different decision variables under different solvers and even within the same solver under multi run.Now I want to reduce the precision on the variables. Currently the continuous variables may search into 20 digits after the decimal point, how can I limit it into maybe the first two digits after the decimal point? Can AIMMS do this?Thanks a lot.

Hello guys! I have a bit of a problem, I am working in a model that includes Gross Cash Flows (in the model defined as Variables, V_GrossCashFlow), which can be positive or negative of course. If the Gross Cash Flows are positive, then a Tax Rate should be applied to them, resulting in Net Cash Flows (V_NetCashFlow). If the Gross Cash Flows are negative, then Net Cash Flow will just be equal to the Gross Cash Flow. For the V_Net Cash Flow variable I am using a definition such as the following:if (V_GrossCashFlow(tr) > 0 [€]) then    V_GrossCashFlow(tr) * (1 - P_TaxationRate)else    V_GrossCashFlow(tr)endif;The obvious problem with this is that the model goes from being LP to NLP. I was wondering if you guys had any idea to model this situation without introducing Non-Linearity. I have tried using binary variables a bit, but every solution I can find with them forces me to define the binary variable using V_GrossCashFlow anyway, so the model is still Non-Linear.I would be very thankf

Hi all, I am going to run the AIMMS with many different scenarios(case data) automatically. In case the solver may not find the optimum solution in some of the scenarios, I wonder is there any parameter or index (such as 0 or 1) I can get after solving each case to indicate if the solver has got the optimum solution?

The reason for my question is that mapping with DEX package for CSV is limited by the number of dimensions possible in a single file and therefore needs the use of multi-level columns.  This limitation requires me to use multiple CSV files for my problem. While using the bind-to and maps-to mapping elements are useful with single line headers and can even be extended with help of .regex, I was wondering if multi-line headers could be adapted to the data exchange mapping elements for csv. Showing a sample table below with the problem that I am facing.    Set4_val1 Set4_val1 Set4_val2 Set4_val2 Set1 Set2 Set5_val1_Set_4_val1 Set5_val2_Set_4_val1 Set5_val1_Set_4_val2 Set5_val2_Set_4_val2 a aa 5 6 7 8 a bb 9 10 11 12 b aa 13 14 15 16 b bb 17 18 19 20 The final value in the table, lets called the parameter X is such that X(set1, set2, set4, set5)Thank youWith Best Regards - Prem 

First, let me introduce myself (as its my first post):Im and Industrial Engineer student making my end of master project studying the scheduling of a production plant. My tutor recommended me AIMMS to solve the MIP scheduling problem and, as you might have guessed none of us used this tool ever So far so good, i have found a scientific paper that solves my particular problem ( i dont think i can upload the paper, so I’ll upload only the good stuff)If AIMMS has a good thing its that it was easy (even for me) to introduce most of the constraints and definitions. So i made (most) of themBut theres one that particularly bothers me, restriction (2) and in a lesser way (7). This ones check the inventory stock at the the end of a certain T time, but if T=0, then it check It-1 (which it doesnt exist). And if T=1, it check It=0The thing is that I created a Parameter that holds the Initial Inventory and i wanted to keep as close as the formulation previously showed, so i went ahead and made some

When I tried to add library from repository, I got the error:Unable to get the list of available libraries from repository.Can you tell me how to deal with it?

Hello to everyone, i have the following problem i can not solve. So on the one side I have consumers that need a certain amount of energy at a time. On the other side I have a generator plant that produce green electricity. The Problem is, that the demand can not alaways be satisfied by the generators. For this I use batteries. The are charged, if there is more then enough energy available.The express this mathematically, I used a if then formulation: For the charging I use:Demand(t) - Generator (t) >= 0 → Battery(t) = Battery(t-1)*(1-self-discharge-coeffizient)+((Demand(t)-Generator(t))*efficiency_Inverter*efficiency_Battery)For the dischargingDemand(t) - Generator (t) <= 0 → Battery(t) = Battery(t-1)*(1 - self_discharge_coeffizient)+((Demand(t)-Generator(t))/efficiency_Inverter)Demand(t), Generator(t) and Battery(t) are variables.self_discharge_coeffizient, efficiency are parameters I do not have any clue how to solve the problem in AIMMS. If anybody could help me, i would be v

Hi there,I´d like to know if SDP and SOCP formulations are supported by AIMMS?, I have not found any reference in the modelling manual nor any examples of that.Thanks in advance. 🙂

Hello, Im looking for a way to create a set where the data inside will be values from 1 to 100 ? What is the formula to put in Initial data ? Thank you 

Hi all, I would like to seek clarification regarding the disparities between MIP (Mixed Integer Programming) and RMIP (Relaxed Mixed Integer Programming) solvers. While I understand that RMIP converts integer variables into continuous variables, I would like to explore any other significant dissimilarities between these two solvers.Specifically, I am encountering fluctuations in the results of one of the variables when utilizing the MIP model as shown in the picture below. Despite the absence of any constraint-related issues, the values exhibit variability instead of remaining constant. Conversely, when employing the RMIP solver, the values remain consistent throughout (as presented in picture below). I am keen to understand the cause behind these fluctuations and any significant disparities between the MIP and RMIP solvers that could potentially explain this behavior. Any insights, explanations, or suggestions on how to address these fluctuations would be greatly appreciated too! Than