Topics about getting started or leveling up as an AIMMS developer. Datalinks, AIMMS language, building apps...
- 544 Topics
- 1,190 Replies
Hello everyone,Could someone please help me look at a way to find the nodal balance equation at a node for inputs having different indices?More explanation: Refer to the diagram below. Assume nodes 1,2, and 3 are set of buses indexed b. Then connecting lines between the buses are Set with index domain (i,j). To find the nodal balance equation at node 2 such that incoming is made equal to outgoing is somehow difficult for me because of difference in indices. For example say node 2, the sinusoidal sine is generator Pg with index b, outgoing arrow is Demand with index b and line flow (LF) indexed (i,j). The index domain (i,j) only shows the sending end bus and the receiving end bus. Hence the nodal balance equation is:Pg(b) = Demand(b) + LF(i,j). How can I find this sum over different indices knowing that number of buses with index b are not equal to the number of line flows?Secondly, the line flow (LF) is made of two characteristics of different indices. the characteristics are Y indexed
Hey. I am trying to implement a plot in a WinUI that displays simulation progress. In this plot, I am showing a variable value changing with simulation iteration (simulation continues until the iteration value has reached a limit). The variable is not in a math program, hence, I believe I can not obtain its value using callback (using RetrieveCurrentVariableValues procedure). Anyways, the variable gets updated at the end of every iteration. Presently, the plot between the variable value vs iteration does not show when the simulation in in progress (or when procedure is running) and appears after the procedure is over. Is there anyway to update the plot when the procedure in running? Thanks. Here is the structure of the procedure I am running: while (iteration limit is reached) solve Mathematical program1; solve Mathematical program2;Update Plot Variable using variables from math programs 1 and 2; (Plot variable to display in plot)iteration = iteration + 1;endwhile;
It seems that for an internal function, I have to specify the arguments with index and size? How can I create an internal function to calculate inverse for any matrix? In this case, do I have to use external function? Thanks.
Hey. I am working to create a tool (GUI) in AIMMS platform. I have multiple pages in Page Manager for developing the tool. In one of the pages, I want to add an ‘Help’ button, clicking which should open the user manual of the tool (in pdf version - not the AIMMS user manual). Is it possible to implement this?Thanks.
Hi AIMMSians,I used to run the GUROBI solver asynchronously a few months ago. But now I am limited to use only one session each time. I use the academic license and the only change is the new academic license delivery, so I guess that is the reason for the new limitation. Can you confirm my guess? if yes, would it be possible to give academics the access for solvingasynchronous sessions in GUROBI and CPLEX?
I encountered this error when running the model. The model is fine, since it works with another set of input data. But with this particular data set, it gets stuck in the Presolving phase, and returns nothing. After force exciting the model, This is the message that it shows in the .err file. Have the same issue when running on the cloud as well.
I am trying to implement the Rough Cut Capacity Planning for an school assignment. I currently have all constraints working except for the first constraint, since I do not know how I can loop over subset of time which is determined by two parameters release date(rj) and due date (dj).
Hi Nice members,Hope you are doing good. I have a question. I have many points and I am constructing a network in AIMMS such that all points are connected to one main source point but not only in direct manner. These points can be directly connected or connected to each other as well to be connect to source point (Such that end point is connected to the points lying in middle of source and end points). My decision variable is binary which tells either any two points are connected or not. Objective is to minimize the cost which actually depends on creating the total shortest connected path which obeys the constraints. I want to know the “xyz” property of any point which actually depends on its connection to the previous node(distance from previous node it is connected to) plus the “xyz” property of previous node. How can I write it in an equation in AIMMS. I do not know the order in which the connections of nodes are going to be happen because it is the optimization problem. It was a l
Hi AIMMSians, I am using the AMD 3995WX processor which has 128 logical processors. I realized that a single instance of AIMMS only uses 64 logical processors as processors are grouped by windows’ limit (64 cores). To use all 128 processors, I can run two instances of AIMMS at the same time. The first instance gets affinity of group0. Then I need to modify the affinity of the second instance to use the second NUMA (group1). Still, I would like one instance of AIMMS employs all logical processors. I assume the same problem exists on servers where the number of logical cores often exceeds 64. Is there any way to bypass windows' processor group policy (i.e. make AIMMS group aware) and distribute the job between all 128 available threads? Note 1: I tried CPLEX and GUROBI solvers. I am not sure if this limitation is related to AIMMS or the solvers.Note 2: I am aware of disabling Hyperthreading/SMT, but that is not desirable.
Hello everyone, I am new to AIMMS and I think I like it because of its graphical user friendliness. I want to use AIMMS to optimize the charging profile of a number of vehicles in a decentralized way such that the original central problem is decomposed to be solved independently as a subproblem by each vehicle. This is to be done for vehicles 1 to N over a number of time steps. I discovered this is difficult for me because the objective function in AIMMS is usually a scalar. Please, how can I do this? thanks
Good morning and a very good day to you!Dear Sir / Madam,Currently, I am running big data using AIMMS for my Final Year Project to produce an optimal exam timetable. My MIP model consists of 1 decision variable, 3 objective functions and 14 constraints.I encountered the same problem for many times when I was running my data. I realized that AIMMS will usually shut down on its own after running for more than 2 hours before even getting the results. I have checked my computer to see if it has any technical problems but I have not found any. Can you please help me with this problem? I am attaching a relevant picture for your further references. I am looking forward to getting a favorable reply from you soon. Thank you for your time and patience.
Hello everyone,i'm just a beginner and have a few problems with aimms. I am investigating a warehouse in which customer orders are split up into partial orders. Each partial order is assigned to a zone.My problem is that Aimms assigns the partial orders to multiple zones instead of just one. In the attachement you can see that a partial order is assigned to several zones. j are the partial orders; z are the zonesIs there a way to say in a constraint that only one value can be assigned? Thank you!!!
Hi, I was using the GeoFindCoordinates function in AIMMS to map a given city name to a lat/lon combination and received an error message all of the time. Then I remembered I was on VPN and maybe there was an issue with the connectivity, so I disabled my VPN connection and tried again and the GeoFindCoordinates was able to execute without a problem.Whenever I am connected to the VPN connection at work, all my outgoing connections must go via a proxy server. Almost all programs I am working use the standard http_proxy and https_proxy environment varaibles, but it looks like GeoFindCoordinates is not doing this.I know there was a possibility to provide proxy settings for activating a license, but I can’t seem to trigger that option (as this seems to use my IE proxy settings).Is there any other way that I can set the proxy settings for this function? Also, could there be a potential for any other functions (like calling webservices, etc) that make outside HTTP(S) connections that they do n
AIMMS functions and procedures use local identifiers to hold the values of arguments. The model editor functions that form the basis of runtime libraries operate on elements of AllIdentifiersThese functions create, modify, and delete corresponding global identifiers in the model. In other words, they do not operate on local identifiers. This short tutorial by @Chris Kuip teaches you to add local identifiers to AIMMS procedures and functions that are created at runtime.
HI, Having the Math Program Inspector is one of the great add-ins of AIMMS. One of the features that I really like is the matrix summary, where I can see the smallest and largest coefficients. However, I want to identify which variables and constraints are involved in those smallest or largest coefficients. One way is to look at the matrix graphical representation, but my model is big and I couldn't find those small coefficients. Now I have some e-14 coefficients that cause numerical instabilities. I was thinking to scale my model, but I would like to find the variables and constraints related to this e-14 coefficient. Is there any way to find the smallest or largest coefficients location in the matrix, without looking at the matrix graphical representation?
Hi everyone,I have been trying to call an AIMMS (academic license) procedure from python although this doesn't seem to work. I got the following code from another thread, which seems to work with a paid license. I also saw on another post that the academic licence might have some limitations in this regard. Is there an API in another language, were I can make Python wrapper around this other language?orIs it possible that AIMMS internally allows to run scripts in some language, in which case a script can be built in such a way that they exchange model parameters/inputs/results with the outside world? Best regards,
hello everyone,i have a question about my aimms project:i have two variables: x(t,k) and y(t,k)now i want to determine, thatif x(t,k) < y(t,k) then y(t,k) = x(t,k)i already know that this is not possible with an if-statement.has anybody an idea? Thanks in advance.Seb
Error message: The constraint "Balanceinv" without a suffix cannot be used inside the definition of a constraint
Hello community!I’m trying to encode my inventory balance constraint on AIMMS but when I click on “Check and close”, I receive this error message: “The constraint "Balanceinv" without a suffix cannot be used inside the definition of a constraint”.Has anyone experienced this problem before and can help me? I would be very grateful!
Hello everyone,I have been using AIMMS for a short time and am still a beginner.When I encode my objective function, the following error message appears : “the scope of index “m” has not been specified”.I have tried several ways to solve this problem but none worked.Has anyone experienced this problem before and can help me? I would be very grateful!
Already have an account? Login
Please use your business or academic e-mail address to register
Login to the community
No account yet? Create an account
Enter your username or e-mail address. We'll send you an e-mail with instructions to reset your password.