AIMMS Language

I want to check if my identifiers have comments written in it’s attributes. I am writing a procedure to do that. But I don’t know if there is any already existing function to get the comments attribute of a given identifier.

Is it possible to use an indexed set inside the domain of Exists?For instance:I have an indexed set IS with index domain (a,b) and subset of c I want to define a new set NS which is a subset of b and c Is it possible to use in the definition of this new set NS the following expression: { (b,c) | Exists[ a | c in IS(a,b) ] } Thank you 

How can you make a Gantt chart based on a binary variable under page manager?

When using the StringToMoment function to calculate the number of hours between two dates and running into something weird: As you can see AIMMS tells me 0 minutes elapsed between 10:00:00 and 11:00:00 My guess is that somehow AIMMS is assuming the referencedate as UTC time, while it assumes the second date as my local timezone.I have also tried to use StringToMoment("%c%y-%m-%d %H:%M:%S %TZ", [minute], "2023-10-11 10:00:00" , "2023-10-11 11:00:00 UTC")To indicate I really want to have the second timestamp as UTC, but that did not help. What is the small/obvious thing I am overlooking here?

Let me first start with one remark: The openAPI client generation is one awesome addition!!! 😀With a bit of a simple workaround I was able to create relatively easy an AIMMS library that was able to import a rather large and complex JSON file that had a quite deep nested structure in it.Now that I have the data in an AIMMS library, I know am trying to write the code that parses the information from the library into the actual AIMMS sets/parameters that I will use in a model.For this part, one of the problems of the nesting is that the generated library works on lots of subsets of integers that restart counting from 0 every time In the following example (that hopefully illustrates it enough)Locations property (contains list of locations):Element 1 in locations list (will map to i_locations=1 in aimms library) LocationName: Location A Products   (contains list of products) Element 1 in productions list  (contains dictionary of name/color, maps to locations::product::i_product=1 in aim

Dear AIMMS, I get the following warning about a predeclared procedure when opening AIMMS 4.97 "Warning: The 'queryMap' argument has a dimension mismatch. This will be treated as an error in a future AIMMS versions. Perhaps the argument should be declared as a Handle.”How can this be solved? Regards, Marit

 Hi, Our model exists of 7 optimizations. However, after the 6th optimization it says that it is terminated by the solver, and it ended up in intermediate non-optimal. What does this mean? Did it end up in a local minimum? Or does it mean something else. Can the results be trusted? If not, how can I solve this? Thanks in advance! 

Goodafternoon, In the figure below the result of a solver session is given. Is their a way to figure out what the program status and solver status imply? I used the CPLEX for solving the model.If more information is needed, don't hesitate to contact me.Kind regards,Ieke Schrader Progress window     

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'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

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

 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 

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”?

Today I got the question: Get elements of a set using set name as a string?This can be achieved using a runtime library.The interface to the data is a procedure with:- input   : the set name- outputs :   o an integer set with the same number of elements  o a string parameter indexed over that integer set with the names of the elements as strings.The tricky part of creating the runtime library is the passing of arguments. Arguments are local identifiers in a procedure, and local identifiers cannot be directly createdusing model editing procedures. This is circumvented by first creating the declaration section, andthen moving that declaration section as a section inside the procedure.An example project which does just that is enclosed.

As you know, the AIMMS PRO REST API can be used to leverage the power of AIMMS applications in other applications.  But how are the AIMMS applications that provide services developed, tested, and deployed?In this short series of small articles, based on a Hello World type of application, it is explained how to develop, test, and deploy an AIMMS app. In addition, it is illustrated how to test this app using clients in other application languages.

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