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1034 Topics
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bestwayyyExplorer
asked in AIMMS Language
exists function with corresponding indices

Hi, Say I have the parameters shown below. I am using the “exists” function to check whether there is a “1” for each category during the time range from 1:00 to 5:00. While “exists” returns a logical value indicating whether a “1” is found, it does not return the index. Along with using the exists function, how can I also find the indexes corresponding to the “1”s in my parameters? Thank you!

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luispinto
Administrator
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ChunyangEnthusiast
posted in AIMMS Language
Complex value assignment efficiency problem

Hi I am trying to do a value assignment in AIMMS. Here is the example: t and i are both the index of set time. n and r are the index for set Node. NodeInTime, needed_value are predetermined parameters. scenario is parameter changing in the process. noted_scenarios_index is a subset of Node. path is a mapping between index (r,t) and set Node. for (n,t)| t<>first(time) and n<=NodeInTime(t) do scenario := 1; noted_scenarios_index := {r | r <= NodeInTime(t) and path(r, t) = n}; for r in noted_scenarios_index do needed_value(scenario, n, t, i) := value(path(r,i), i); scenario := scenario + 1; endfor; endfor; I used debug move to check and surprisingly, the slowest part is: needed_value(scenario, n, t, i) := value(path(r,i), i); when it runs to this line, ‘scenario’, ‘n’, ‘t’ are determined and it took more than 30s to run this line….. So I don’t understand why it’s so slow. I also tried using an additional parameter like: addition(i) := value(path(r,i), i); needed_value(scenario, n, t, i) :

181
Chris Kuip
AIMMSian
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m.dwiantoExplorer
asked in WebUI
Adjust column width for table inside webui tabbed page widget

Is it not always possible to adjust column width of a table inside tabbed page. it can be adjusted when accessed through the page itself. is there a way to enable the column width adjustment from tabbed page widget?

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Edo Nijmeijer
AIMMSian
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delta2295Explorer
asked in AIMMS Language
Unpack .aimmspack file

I was wondering if there is a programmable way to unpack an aimmspack file, e.g., MyAimmsProject.aimmspack, without launching Aimms? Looking for something like AimmsCmd.exe /Unpack "MyProject.aimmspack" -o "Path\To\Unpacked\Project"

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denghaiyingEnthusiast
asked in AIMMS Language
How to send a presolve solution to its original MathematicalProgram?

Here I find a problem: when I use GMP::Instance::CreatePresolved to solve a MathematicalProgram , the solution I get belongs to the Presolved MathematicalProgram rather than the orignal MathematicalProgram. My code is as follows: MyGMP := GMP::Instance::generate(MarketDA);MyGMP_Pre := GMP::Instance::CreatePresolved(MyGMP,"GMP1");MySolver := GMP::Instance::CreateSolverSession(MyGMP_Pre , "Solver1" , 'CPLEX 12.3'); GMP::SolverSession::Execute(MySolver); GMP::Solution::RetrieveFromSolverSession(MySolver , 1 ); GMP::Solution::SendToModel(MyGMP,1); There is an error report on the last line shows the solution 1 is not exist. Is it possible to send the solution 1 to “MyGMP” model ?

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Marcel Hunting
AIMMSian
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gorkemAce
asked in Algorithmic Capabilities & Optimization Modeling
Drastic change in the number of variables on the Progress Window right before the solve

Hi, Using the AIMMS version 24.5.9.4. I have put pretty tight conditions on my index domain on purpose, but the model generation phase takes about 20 mins and # variables on the Progress Window reaches up to 55 million, which is a very surprising number for me because of the reason above. Then right before the solve process it instantly decreases to 679K, which is much closer to what I’d expect. Then the solve process takes only 5 secs. So 20 mins for the model generation, and then 5 secs to solve, but what I am really wondering is why would the number of variables inflate this much and then instantly decreases right before the solve? Can anybody explain the possible reasons? Please see the pics below. Best,Gorkem

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bestwayyyExplorer
asked in AIMMS Language
converting parameter to index

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.

151
gabiservidone
Administrator
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Serval2501Explorer
asked in Algorithmic Capabilities & Optimization Modeling
Issue with Model Feasibility in CPOptimizer 22.1

Dear community, When I try to execute my model, I receive the following message: Warning: After zero branches CPOptimizer 22.1 concluded that ModelObjective is infeasible. I don’t understand what is causing this issue or how to resolve it.I am aware that some parameters are currently unused, but they will be needed for future adjustments once this first part is working. Does anyone have any insights on what might be going wrong and how I can fix it? Best regards,Louis

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Marcel Hunting
AIMMSian
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denghaiyingEnthusiast
asked in Algorithmic Capabilities & Optimization Modeling
How to change the Gap of a SolverSession by GMP Method?

I have met such a problem: When I use “GMP::SolverSession::SetOptionValue(SCUCSolver,"Polishing_relative_MIP_gap",0.0001)” to Set the Gap of a MIP Mathematical Program, the solver returns a solution with gap of 0.99% which is larger than 0.0001. I have also tried to use “option MIP_relative_optimality_tolerance” but it still didn’t work. How do I so this? Thank you

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Marcel Hunting
AIMMSian
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denghaiyingEnthusiast
asked in Algorithmic Capabilities & Optimization Modeling
How to use GMP::Row::Deactivate in a MIP Mathematical Program?

I Want to solve a MIP Mathematical Program without some of the constraints by use GMP::Row::Deactivate, but the Program Status return Integer infeasible. However, when I Replace GMP::Row::Deactivate with GMP::Row::Delete, the Program can be solved. I could’t understand the difference between GMP::Row::Deactivate and GMP::Row::Delete. My code is as follows: SCUC_Instance := GMP::Instance::generate(MarketDA_MP);GMP::Solution::DeleteAll(SCUC_Instance);SCUC_InstancePre := GMP::Instance::CreatePresolved(SCUC_Instance,"SCUC");GMP::Solution::DeleteAll(SCUC_InstancePre);NFGConstraintsSetRowNum := GMP::Instance::GetRowNumbers(SCUC_InstancePre, NFGConstraintsSet); !NFGConstraintsSetRowNum is a Subset of Integer with index as nk for nk do GMP::Row::Deactivate(SCUC_InstancePre,nk); endfor;endif;NFGVariablesSetColumnNum := GMP::Instance::GetColumnNumbers(SCUC_InstancePre, NFGVariablesSet); !NFGVariablesSetColumnNum is a Subset of Integer with index as nv for nv do GMP::Column::Freeze(SCUC_InstanceP

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Marcel Hunting
AIMMSian
Chris Kuip
AIMMSian
Chris KuipAIMMSian
posted in AIMMS Language
Zip lib

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.

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Chris Kuip
AIMMSian
rahmat
rahmatAce
asked in AIMMS Language
display multiple variable data in a parameter

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

243
gdiepen
AIMMS Champ
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Michael ColeExplorer
asked in AIMMS Libraries
Create library for combining multiple math programs?

I have multiple math programs, each related to a different energy supply sector.. I want to keep their development and version control independent. Is making them into libraries a reasonable way to combine these otherwise independent math programs?

291
Chris Kuip
AIMMSian
Edo Nijmeijer
AIMMSian
Edo NijmeijerAIMMSian
posted in WebUI
Upcoming (font) styling changes that might influence your WebUI apps and the applicability of custom CSS

This week (with feature release 25.2.1) we will be releasing a change that is both big and small at the same time: we will stop using the Roboto, Roboto Condensed and Montserrat font families for WebUI and migrate to a font family known as Inter. These changes are part of our ongoing desire to keep WebUI's appearance up-to-date and to offer a better User Experience. They mark the start of a range of other changes, to the look-and-feel but also to how you can use WebUI, that should all achieve this same goal. Inter comes with some advantages, for you as an end-user of WebUI: Using Inter for the entirety of the UI will result in a more consistent look, making WebUI a more balanced experience, also for app developers. Inter was designed to feel modern and has features to enhance and adapt readability depending on the font size and weight. Inter can be delivered to your browser from fewer and smaller files, resulting in the best possible page loading performance. Despite all these large cl

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Edo Nijmeijer
AIMMSian
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olusegun.adenijiEnthusiast
asked in AIMMS Libraries
CONOPT 4.1 Library not uploaded

Good morning all. I just brought out an old program I have written over a year ago to run it and it gave an error: ‘The CONOPT 4.1 library has not been loaded because: Solver initialization failure.’ Please, what can I do to remove the error. Thank you.

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MarcelRoelofs
AIMMSian
Chris Kuip
AIMMSian
Chris KuipAIMMSian
published in WebUI
Exit AIMMS WebUI applicationHow-to

At User Support we occasionally get questions about the termination of WebUI sessions; for instance as follows: We have a project where the premaintermination and maintermination both contain the statement “return 1”. Separately, we have a library in which we want to run some checks and empty some parameters in the library pre termination. However, we observe that when the app is uploaded, the PreLibraryTermination and LibraryTermination are not ran. We’ve noticed this because when re-opening the same app within a few minutes, the data session is still active, and parameters that should be empty because we empty them both in the library initialization and termination, still contain data. Understandably, if you are not aware of the termination protocol of AIMMS WebUI sessions, this can be confusing. Let me share some details about the termination protocol for an AIMMS WebUI session first: Background: An AIMMS WebUI session consists of two communicating processes: A process in the browse

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Chris Kuip
AIMMSian
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AIMMS Partner
danileidelmeijerAIMMS Partner
asked in AIMMS Libraries
Reupload standard Excel functionality fails

Hi community We use standard Excel functionality to download a file of the following format: Then we try to reupload this file after having made the following adjustment (we manually adjusted the columns A and B and copied the values in A2 and B2 from other Excel): However, this reupload resuts in 0 changes being made to the table in the WebUI. What could be the reason the reupload fails to read in the 1000?

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MarcelRoelofs
AIMMSian
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hariharangatechExplorer
asked in Algorithmic Capabilities & Optimization Modeling
Opening Large Models

Hi, I created a large model by manipulating the .ams file via notepad. The total file size is 8MB. Around 0.1 million variables and 60K constraints. Since, I did not create this perhaps from the interface - it is taking a lot of time to open. Also, say I know that the model is fully correct(syntactically and otherwise). How can I call and run it via python? I am using academic license. Please do give me a short tutorial for this. I did see the REST API but it seems too complex. Is there perhaps the CMD version of running? Can I run academic license models via CMD? If so, I think I can use the subprocess method. Basically, 2 question: A large custom manipulated .ams file is taking too long to open. It is in fact not opening and is in “Not Responding” state for too long. How to call AIMMS model and run from python. ThanksHariharan

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Marcel Hunting
AIMMSian
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AIMMSian
dsalakirovaAIMMSian
published in AIMMS Support Updates
Connection to the AIMMS licensing database for AIMMS older than 4.66 and AIMMS License Server older than 4.0.0.66

The innovation In order to provide additional security for our licensing database, we have enabled encrypted connection to it from your AIMMS applications and from the AIMMS License Server. Who does it affect and how? Users of AIMMS versions older than 4.66 and users of AIMMS License Server version older than 4.0.0.66, including for PRO on premise (no impact on AIMMS Cloud). These two groups of products will not be immediately able to establish connection with the AIMMS licensing database. Further to our License Agreement, for licenses activated as personal nodelocks , AIMMS will try to connect to the database on every usage. If there are more than 60 days without this connection being established the license will get locked. For licenses activated as machine nodelocks, no matter if activated in AIMMS or in the License Manager, the connection to the database gets established when the time for updates comes. Licenses activation or deactivation, when done online, will always require conn

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AIMMSian
Jan-Willem
AIMMSian
Jan-WillemAIMMSian
posted in Integrations and Data Exchange
What features would you want to see in aimmspy?

This year we will develop and release aimmspy, a Python library that will allow you to combine the power and convenience of Python with the well-known strengths of AIMMS. We already spent quite a lot of time designing the functionality of this library, but we are keen to hear your thoughts and ideas. And we are purposely not sharing our ideas to prevent directing your thinking 😎. Can you please share your thoughts on what you would like to see in such a library, as reply to this post? And if you prefer to share your ideas in a live conversation, please email me at j.w.van.crevel@aimms.com. I will then reach out to make an appointment. Looking forward to hearing your thoughts, needs, etcetera!

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Jan-Willem
AIMMSian
Jan-WillemAIMMSian
posted in AIMMS PRO On-Premise & AIMMS Cloud
How about an LLM-powered PRO Jobs Page?

We are rebuilding the PRO Jobs Page, see also this post. While working on that another idea came up, replacing the 'filtered list’ of the current Jobs Page with a LLM-powered chat. And we generated a ‘paper prototype’ of this. Can you please take a look and let us know: what pros and what cons do you recognize? would you prefer this over the current ‘filtered list’? suppose we would offer it as an alternative, for what tasks would you use it and for which ones use the ‘filtered list’? Here is the ‘paper prototype’, illustrating various dialogues from various roles. Each dialogue is designed to address the specific needs of the user role, demonstrating the AI-powered chat's ability to understand context and provide actionable information and solutions. We trust that with that it is self-explanatory. Thanks for your help! Paper Prototype for Jobs Page powered by GenAI Dialogue 1: End User - Checking Task Status User: Hi, can you tell me the status of my current sessions? AI: Of course! H

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Jan-Willem
AIMMSian
C
C123Explorer
asked in AIMMS Language
Error message: "abort is not in the set AllIdentifiers".

Hi everybody, Recently I updated AIMMS to version 24.6.1.6. Now I get the error message “The element 'abort' is not in the set "AllIdentifiers", see also the option warning_explicit_element_not_in_set.”. Does anyone know how I can solve this error? It happens when I use a call back function and want to assign “abort” to the CallBackReturnStatus. Thank you in advance!

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C
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AnneEnthusiast
posted in Algorithmic Capabilities & Optimization Modeling
Foood Menu Optimization

Hi, i have found the reason behind infeasibility, there were corrections to be made in one of the constraint. Thank you for helping me. I need further assistance on this, I will display my project here on what i have done. I have declare the ingredients and the foods lists. The sodium content is of the food, not of the ingredient. After declaring the ingredients, i am connecting the ingredients with the food that it belongs to (in parameter called as recipe): Simple example, bread slice the ingredient not much, so its just bread slice. For tuna sandwich it is bread slice, tuna and mayonnaise i have tick across and i thought AIMMS can read the ingredients as the subset of the respective foods. I find it somehow correct by the way AIMMS show this. Linking with the constraint Callback the parameter “recipe” in one of the constraint as i am using Linear programming model to solve this problem. And the decision variable X includes (days, s-meals, food, ingredients, patients). The result im

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Jan-Willem
AIMMSian
Jan-WillemAIMMSian
posted in AIMMS PRO On-Premise & AIMMS Cloud
Can we have your input on the AIMMS Cloud Jobs page?

We are working on a redesign and rebuid of the Jobs page in AIMMS Cloud. Can we have your input on a few topics? What are you using the Jobs page for? What changes and improvements would you like to see there? What existing features would you like to see moved from other parts of the AIMMS Cloud portal to the Jobs page? We are looking forward to your input!

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Jan-Willem
AIMMSian
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PankajExplorer
asked in Algorithmic Capabilities & Optimization Modeling
Need suggestions on tightening/improving the transhipment model

I am new to AIMMS and working on a transhipment model with multi product scenario.Need some help and suggestions on tightening the model.Any specific constraints, parameters that I should consider?

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