AIMMS Language

Hi,I have a parameter read from a CSV file. The first column contains the index list, and the other three columns contain the data. However, I need to use the second column as a second index to differentiate between each hour after the parameter is loaded. I was wondering how this can be done in AIMMS. Please note that using the second column as an index in the first place when I am reading the the CSV file is not viable due to other constraints. Please see the attached photo for a better understanding of the issue.Thank you. 

Hello AIMMS Community,This post introduces the AIMMS Zip Library, a tool designed to streamline your file management tasks. This library provides functions to zip and unzip folders, making it easier to handle large sets of files efficiently.Key features:Two AIMMS procedures  zip::pr_zipFolderToFile To compress a folder into a file  zip::pr_unzipFileToFolder To expand a file into a folder These procedures provide the same results on Windows and Linux.Workings:On Linux, it is assumed that zip and unzip are installed. On Windows, the Powershell Compress-Archive and Expand-Archive are used.Installation in your application: please use a download links provided in this how-to article.We hope you find use for these commands. 

Dear AIMMS expert,Is it possible to display several variable data with a single parameter?Thank you very much.

Hello, I am a beginner at using AIMMS and have my sets, parameters and variables all sorted out. I am, however, stuck with one constraint. I have a variable x(p) (so x(p) needed) and parameter d(p) (max capacity (p)) and want to have a constraint x(p) <= d(p), but without havin to use a sum. How do I so this? Thank you. 

One of the most frequently asked questions in the process industry is whether a given stream is measured by volume or weight. With AIMMS, this can be easily determined by examining the unit of measurement (UoM) assigned to the stream. In AIMMS, UoMs are managed as data and stored in what are known as unit parameters.For example, consider three streams: a, b, and c. The units for these streams can be specified in AIMMS as follows:data { a : [kg], b : [ton], c : [m3] }To determine if a stream is a weight, you need to check if its UoM is commensurate with the base unit of weight. Assuming we have a function fnc_isCommensurate(up_a, up_b), you can use the following expression:fnc_isCommensurate(up_strUnit(i_stream), up_baseUnitWeight)This will indicate for each stream whether it is measured by weight.Using the AIMMS intrinsic function AtomicUnit, the fnc_isCommensurate function can be implemented as:fnc_isCommensurate := AtomicUnit(up_a) = AtomicUnit(up_b);

Machine efficient data sources often identify objects via numbers.  Human friendly representations of same data uses names instead. When exchanging data with both machine efficient data sources and human friendly data sources translations are common.The attributes binds-to-display-name and range-display-name, introduced with AimmsDEX 24.6, facilitate translations between element representations, for instance a translation from number to name and visa versa. InterfaceThe running example uses locations and connections, and its interface looks as follows:The locations are actually numbers, and the annotation webui::ElementTextIdentifiers translates these numbers to names in the UI. InputThe input is in SQLite tables, such as: The input identifies each location by its number, and has a name as attribute​​​​​​ Writing Excel directly: With this data, it can be directly written to an Excel sheet.The mapping file this table looks as follows: And the corresponding data sheet that comes out of i

The other day a customer was asking about the statements empty, cleanup, cleandepedents, and rebuild.  In addition, that customer wanted advice on memory management when running multiple data instances for the operations research problem at hand.These two questions will be handled in two subsections below.Quick overview of some data management functions. If S is a set, index i in S, and parameters P(i), Q(i,j) exist,then the statementEmpty S ;will remove all data from S, P, and Q.There is a variant of the Empty statement that operates onsubsets of AllIdentifiers. Let the set sIds, subset of AllIdentifiers, be { P, Q }.Then the statement:Empty sIds ;is implemented as emptying the data of P and Q, not of sIds.Additionally, if S used to be data { a, b }, but is now { b },and P used to have data { a : 1, b : 2 }then:('a':1 ) is called an inactive element of P.To remove the inactive data in P, there are two alternatives:Alternative 1. The statementCleanup P ;will remove the inactive data fr

This week, our partner CQM published a great use case on "valorization." The article is in Dutch, so I asked ChatGPT to translate it.https://cqm.nl/nl/cases/vips-maakt-planning-vion-datagedreven In agriculture, food production, and food processing industries, "valorization" is crucial. It increases the value, utility, or profitability of a product. In the meat processing industry, this means utilizing every part of the animal as efficiently as possible and making the most out of the meat. It’s a highly complex process with many variables. Together with meat producer Vion, CQM developed the VIPS application, which has made Vion's planning data-driven.Vion Food Group's largest production site is located in Boxtel. Vion is an international producer of meat, meat products, and plant-based alternatives. From this location, fresh meat and processed meat products are supplied to national and international retailers, food service industries, and the meat processing industry. Due to their scale

Hi, everyone! I’m trying to import a parameter based on a excel sheet. The cell is empty and the parameter is set with a default value of inf, but the parameter keep assuming value of zero. There’s anything that I can do to, if the cell is empty, the value assumed be different than zero?I don’t know if this should happen or if it’s an issue that has already been fixed. I’m using the verison 4.85, by the way. Thank you very much!

I have been trying to construct a optimal power flow(OPF) model. I refer to the OPF model in “How-to”, and add time terms( 24-hour optimisation cycles), energy storage and renewable generation to the model. However, there is an error of “The definition of constraint contains a goniometric function, which cannot be handled by BARON” in my model. This problem did not appear in the original model even though it also has geometric functions.Does anyone know why and how to avoid such errors? Thank you very much!

Can AIMMS achieve the function that copy one Section in Project A to Project B?  For example, there are two projects that need to use the energy storage model. I've built an energy storage module in Project A. How can I copy this module to Project B to avoid repetitive modeling？

I have an excel file with many spreadsheets. Almost all of them have tabular data information. But one of them has information like the image below. I read the documentation I found about dex, but I couldn't find out if it is possible to import using this format and how to do it.  

I am trying to do some dataframe operation through AIMMS. I am giving some sample example. Say, only one row is there in a dataframe. The values are TC130 and SF520. Say the parameter name is ```pMap(tdc1, tdc2)```.  I would like to run a for loop on the second column value, i.e. on tdc2. Here it is SF520, I'll extract the corresponding value of SF520, which is TC130. Now I'll check in another dataframe, where quantity has been given for TC130. The parameter is ```p(tdc1)```.  If TC130 belongs to that dataframe, i.e. if p(tdc1) > 0 then I'll create a parameter on tdc2, say p(tdc2) and assign value 1 to that else 0.How to write this types of procudure in AIMMS. In a nutshell. I have two parameters p(tdc1, tdc2):= {(tdc1, tdc2) : 1} and p(tdc1):= {tdc1: quantity}. This is simple case.  

We have multiple projects and I’d like to use the same code (that i’m writing) for each project. In this code, ideally, it would write the Project Title to the database, along with some other data. How can I access that Project Title via the aimms code?

parameter Demo_Lab(c,l) is the element of c. So to declare the constraints, I insert this equation at the constraints definition.In this picture, I inserted the parameter in index domain of variables. So, I have question. What’s the differences between these two type of declaration? and what is the condition to use each of it. Can someone explain to me?

I am using SetElementRename to rename one of my elements. However, each time I run the function, it claims that the element is specified in the model and cannot be renamed, but this element is not hard-coded in any part of the model.Has anyone actually got this function to work?

Dear All,I want to apply an interpolation formula to determine the value of a parameter. For example, a parameter that states the emission limit to achieve a net zero emission system has a value in 2025 of 1000 tons of CO2 and in 2050 the emission target is 0. How do I fill in the emission value between 2025 and 2050?Thank you for the advice given.

Hi,I am currently working on a project using AIMMS, and I have a question regarding the declaration of data as Subsets and Parameters. I understand the basic concepts, but I am a bit confused about the difference between Subsets and Parameters.In my understanding, both Subsets and Parameters seem to serve similar purposes, but I am sure there are distinct differences between them. Could someone please explain the difference between Subsets and Parameters in AIMMA, and provide some examples of when to uses each?Thank you in advance for your help!

Hi @AIMMS Community Team, ⁠For one of our bespoke apps the name change file is way larger than it needs to be. Do you know if there's any AIMMS functionality to do a one-time compression/clean-up for a project?

I got a question from @José Fernando Bosch Moreno and I thought it would be interesting to share here.I would like to develop an application for financial projections in which the user can add new parameters that contain formulas based in existing parameters. This is important because generally new calculations have to be developed by information specialist and the time to develop and include new formulations is long. I have developed information systems in which the user can add new calculations and I think AIMMS would be a good alternative to develop financial systems in which the user can add new formulation from the user interface without the need of an information specialist.

Show the infeasibility reason as in Excel it will have the command to show that the cell is wrong in red, how to apply the concept in AIMMS as to show that the infeasibility in which part clearly. Also to get suggestions from AIMMS on what needs to be changed by what.

 equivalent sparse data and list dataToday I got a question to turn a sparse table into a row of lists, as illustrated above.As you can see, the data is the same, just presented differently.To transform the left representation to the right, it helps to work with an indexed set: A list has positions 1 up to max size of the list; which is no more than there are columns:With that we can declare the essence of the list structure as:There are two ways to fill the data, first a more explicit one:As you can see, this requires two references to the indexed set, the first one to limit the elements visited, and the second one to get the position of i_col within the indexed set.By binding the index i_col not to the set s_cols, but directly to the indexed set is_colElems(i_row), the transformation becomes more compact.Once the essence is constructed, we can copy the values, and create a string parameter to present the data actually in list format:  

Hi every oneI would like to implement a cost function VS CPU time curve similarly to the following figure. How we can do it?thanks for your support 

When a ‘print’ button is pressed, an error message pops up as shown below: Code under the procedure as shown: PR_Verify_PDF_Printer;PrintStartReport(sp_WeeklyReport_Cover_Title);! Print coverPrintPage("r::Weekly Report Cover");! Print summaryPrintPage("r::Weekly Report Summary");for i_WeeklyReport_PrintableMonth do    ! Set month    ep_WeeklyReport_Month := i_WeeklyReport_PrintableMonth;    ! Generate report    pr_WeeklyReport_GenerateReport;    for i_Report_PrintableAffiliate do        ! Set affiliate        ep_WeeklyReport_Affiliate := i_Report_PrintableAffiliate;        ! Generate Affiliate report        pr_WeeklyReport_GenerateAffiliateReport;        ! Print page        PrintPage("r::Weekly Report");        if p_WeeklyReport_PrintExtraGraphs then            ! Print page 2            PrintPage("r::Weekly Report 2");        endif;    endfor;    ! Print monthly totals page    PrintPage("r::Weekly Report Month Total");    pr_WeeklyReport_ClearTotals;endfor;PrintEndReport(); What might

Today I got a question on support whether the unit of a constraint influences the shadowprice; for instance, what is the consequence of using [ton] instead of [kg] on the unit of constraint for the shadowprice.A small example illustrates the effects: Variable x {    Range: free;    Unit: kg;}Constraint limX {    Unit: ton;    Property: ShadowPrice;    Definition: x <= 5[kg];}Variable o {    Range: free;    Unit: kg;    Definition: x;}  The base unit of Mass is kg. Running the model, the shadowprice returned for limX was 1; indicating that increasing the rhs by 1 unit (kg), will increase the objective by 1. Then I changed the unit of limX to ton, and solved the model again.The shadowprice returned was 1000; indicating that increasing the rhs by1 unit (ton), increased the objective by 1000. See also: https://documentation.aimms.com/language-reference/optimization-modeling-components/variable-and-constraint-declaration/constraint-declaration-and-attributes.html#constraint-levels-bounds