Optimization Tooling

Dear AIMMS-community,first, I’d like to thank you for the great software. I think AIMMS is great. About the problem. It's probably easy for the experts among you to solve. So far, I haven't found the right solution. I am developing a model to analyze cost efficient pathways for the ramp-up of production plants for renewable fuels over several periods (t). I consider different plant generations (g), where a lant of a newer generation has "better" characteristics than the ones of the older generation.The addition of plants into the system is defined by a free variable "PLANT_COMMISSIONING(t,g)". Based on this, the overall plant infrastructure is defined with various other variables and constraints. I would now like to integrate the "behaviour" that a new plant generation can only be built if plants of the previous generation have been built beforehand (upscaling), e.g. if a minimum number of plants of the previous generation have been built beforehand. I am looking for an MIP approach fo

Hi,I am facing some issues while trying to fetch the data through a Oracle DB. I have written the connection string as“"Driver={Oracle in OraClient12home1};Dbq=*****:PORT/*******;Uid=*******;Pwd=*******;"It is showing the following error in database procedure"Read_IO_fines" failed: Error opening datasource ‘Driver={Oracle in OraClient12home1} Dbq=*****:PORT/*******;Uid=*******;Pwd=*******;’, ODBC Error: IM002 [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified.” Am I missing anything. I have Oracle Client installed in my laptop. 

Is there a parameter that shows if the solution is unique when using CPLEX? 

Hi All, Is there any way to import the data generated in ‘Jobs’ section in PRO Environment to AIMMS Model? The aim is to track the usage of apps & their users. Regards,Vishwesh Patil 

I am trying to open a project that was written in AIMMS 4.37 with AIMMS 4.88. Upon opening it, the window shows ‘compiling’ at the bottom for a few seconds before crashing and closing down. Is this to be expected?Is AIMMS 4.88 compatible with projects written in older versions?Should I expect to see an error message instead of the whole program crashing? Any help would be much appreciated! Thanks,, Sandip

Hello AIMMS community, I am trying to create a mapping file to read a JSON file using Data Exchange Library. The JSON file is structured as follows:Data: {"CaseTable": [        {            "Case": 1,            "Specification": "Specification 1"  },        {            "Case": 2,            "Specification": "Specification 2"  }]’ "PriceTable": [        {            "Contract": "X",            "Specification": "Specification 1",            "Price": 100  },        {            "Contract": "X",            "Specification": "Specification 2",            "Price": 200  }]}As can be seen, the JSON file includes two tables: "CaseTable" and "PriceTable". I want to read price from PriceTable and assign it to the Price_Parameter(i_case, i_contract) which is indexed over “Case” and “Contract”. For example the value of this parameter should be 200 if the Case 2 and Contract “X” is selected:Price_Parameter(2, X)=200. Case 2 is related to the Specification 2 (according to the CaseTable) and the price

I have a multi-indexed parameter, say pMatrix(i,j). I want to efficiently get the first element of the matrix.Applying the First-operator (i.e. First((i,j) | pMatrix(i,j))) did not work; it results in the following error: “The iterative operator first can have only one iterative index.”I can think of some workarounds (such as to start by finding the first i, and given this i finding the first j), but this is quite cumbersome, especially when there are more than two indices (in our project we sometimes have up to 7 indices).How should this be elegantly addressed?

This article discusses some elements from the popular software methodology Test Driven Development in relation to the AIMMS Library AIMMSUnitTest. Gather requirements from stakeholders What are small examples? What are the edge cases, including error cases, performance? Implement requirements as unit tests and see them fail! Development Write the code for the functions Execute tests and see them pass! Refactor until performance is acceptable. Repeat Read more...

In the new version of  aimms, the “data manager button” does not exist. I used to run multiple instances as a batch file using the data manager. I saw the “select multiple case files option” but I could not figure out how to use itto run a set of instances automatically. I appreciate any help in advance.

Existing successful applications often have several features. To realize all these features there is a significant body of code.An application developer may be faced by a small change that causes significant differences in runtimes.Examples of such small changes are:a change in data,  a code hotfix,  a switch of computing environment, or two different persons operating the application.The location of the code where these performance differences manifest themselves may not be obvious. Facilitating the adage: measuring is knowing: the AIMMS engine provides the diagnostic tool: AIMMS Profiler.The AIMMS application ProfilerRunCompare is a small tool to compare two profiler runs. Come and check it out here.

Hey! I'm trying to export using AXLL and have been able to write single variables and simple composite tables, but can't figure out how to slice a variable. I'm not sure if this is something I haven't learned about Sets or something with WriteCompositeTable.I want to do this:my_set := {A(x, ‘Blue’), B(x)}axll::WriteCompositeTable(              IdentifierReference : my_set,             TopLeftCell : "A1");It's the ‘Blue’ part that I can't figure out.Thanks in advance!

Hello,I have a question related to writing a result to excel. I know how to write a matrix from a single parameter to excel, however I have trouble constructing a single table where all values match. If I have a parameter location(city, xy), where city is a set’s list, while xy has two columns (latitude, longitude), and I would like to combine with parameter Client(city,client), and parameter DistanceClient(city, distance), and parameter ClientDemand(client, poroductdemand), how do I save this data into one table where the rows and columns match?NOTE: each city has different number of clients: city1 has 4 clients, while, city2 has 8 clients, etc.How to obtained the following matrix in excel that looks like this:               latitude     longitude    client     distance   productdemand  city1city2city3….cityn  I’m really appreciate your help :)Kind regards

Hello AIMMS Community!I’m looking to understand if it’s possible for AIMMS Data Exchange Library to read an excel file that is structured something like this (modified from the sample on the DEL documentation for EXCEL):In this structure, we have an excel sheet called “Table1”. The table on this sheet has two columns that map to an index (set1 [i], set2 [j]), two parameters that are defined over these indices (d1, d2, d3) and a child table that uses the two defined indices and a third index for time that maps to a parameter p_test(i,j,k) . Where k is defined by set in columns (Time-1, time-2, time-3). I’ve been able to successfully read d1 and d2, but I’m having trouble understanding if it’s possible to read a third index in the column.  The current documentation does not describe thisThe motivation for using DEX in this case is that we have have existing XML files that read the same data from JSON (output from database calls). We’d like to leverage these XML files to create excel mapp

Dear AIMMS community group,I’m currently working on modelling an Inventory Routing Problem in AIMMS based on below model formulation to minimize the total transportation and inventory cost.I have created a project in AIMMS as enclosed, however despite no errors I don’t receive a solution (solution is total cost of 0).Therefore, hoping someone can support to have a look at my model and advise on what might be wrong and how to solve to generate the solution.I’m attaching you my AIMMS project as well as the model formulation that I’m using.Thanks a lot in advance!

Dear reader,I would like to inform our users about the rationale for migrating from Amazon to Azure. Is there an easy explanation for this migration?Other question is whether the new Azure environment has more powerful hardware? CPU / Memory etc.?Look forward to your repliesMany thanks in advanceBest regards,Nort

I see in the release notes that the default value of a parameter is now only available if it is specified.However, I always use this option to empty selection boxes. I tried addding '’ as a default value, but that still does not allow me to select the “Default:: “ option in the dropdown.So my question is “What should I now do to empty my selectionbox (and show the data for all possible values of the parameter - instead of only for the selected value (location in my case)? 

Hi everbody,I want to generate an integer parameter that contain whole data from the table in one line, where the values for the same row are sparated by “,” and values of each rows are separated by “|”.Wish the final result looks like that:“1, 2 | 3, 4 | 5, 5 | 6, 7 | 8, 9 | 12, 0”Table:Location\XY Lan Long Place1 1 2 Place 2 3 4 Place 3 5 5 Place 4 6 7 Place 5 8 9 Place 6 12 0  The data is located in the parameter(cityID, XY). Where CityID corresponds to list of cities, and XY has two possible values “Lan” and “Long”.Thank you for your help :)Cheers,

Hello,I have a problem with Aimms, I tried to program a Gantt Chart and a Calendar. For excercise I followed the Demos. So my question is after I wrote the program where can I see the Calendar or the Gantt Chart ?Do I have to use the widget or install some other extension ? Thx for your help

Hi, Is there any attribute which can ensure that only nondefault values are written to Excel?Like axll:WriteTable function has writeZeros argument and if it is set to 1 then zero cells will remain empty. Thanks,Lilla

Hi, I have only started using AIMMS recently and in a couple of recent studies I keep getting an infeasibility error - see belowCan someone please tell me what I am doing wrong and what I need to do fix it please?Many thanks Chris Wellings

Hello everyone,  Is there a way to use a discrete uniform distribution inside of Aimms? I know there is a uniform distribution but it gives me real number values for my parameter. Instead i just want integer values to be drawn from the uniform distribution. Is this possible?  Thank you for an answer. Kind regardsAlex

Hello everyone,  I have an Element Parameter PredecessorOperations(i_operation) that holds the value of the operation that has to be executed before i_operation. With the following statement i want to check if the EP has a value or not:  if (val(PredeccesorOperation(i_operation)) = 0) then….endif; However this only works if all values of the Ep are empty. If any operation gets assigned a predeccesor (e.g. Operation1) then i get the error: Cannot compute the value of string “Operation1”. If I would casually formulate the code it would look like this: if( PredeccesorOperation(i_operation) is empty ) then ….endif;So my question is: What operator do I need to use in order to check if the parameter has any value or no value assigned? I am thankful for any advice you might have. With kind regardsAndrew 

Hi folks,I’m doing some tutorials in AIMMS and I find that the data exchange library is missing from my AIMMS version. Can anyone point me how to install it? This is what I currently see: ThanksLS

Hi everybod,I have a quick question and hope you can help me.I calculate in my model the optimal stock level depending on the period and szenario specific demand.The inventory level is defined as follows: Inventory_PreviousPeriod + ProductionQuantity_CurrentPeriod (also a variable) - DeliveryQuantity_CurrentPeriod.How is it possible to preset the variable stock for the first period to a fixed inital value (in this case the opening inventory)?I would be very grateful for your answer!Best ragards, Hans