Optimization Tooling

Hello,  I would like to change the checkbox background color from blue to other. Which class should I change? Thanks

Dear all, In my model, I work with multiple factories. Each factory has a minimum lotsize requirement, meaning that IF a product run is initiated, it must be at least xxx big. I tried to put it in as follows: I have a parameter MinimumSKULotsize(f), which specifies the minimum lotsize per factory; I have a binary variable ProductInFactory(f,p,t), where 1 indicates a production run of that product at that factory in that time unit, and 0 does not. I have a variable ProductionAllocation(p,f,t) which indicates how much of each product is allocated to which factory at which time unit. I tried to add the constraints: SKULotsizeConstraint0 with index (f,p,t) | ProductInFactory(f,p,t) = 0 and definition ProductionAllocation(f,p,t) = 0 SKULotsizeConstraint1 with index (f,p,t) | ProductInFactory(f,p,t) = 1 and definition ProductionAllocation(f,p,t) >= MinSKULotsize(f) However, I am gett

I run Power System Optimizer (PSO) developed on AIMMS. The current version of AIMMS we have is 4.30.5.814 on the windows server. The software ran with no issues till last week. However, after probably the server update, AIMMS crashes each time I read input files and throws the following error: the thread tried to read from the virtual address for which it does not have the appropriate access. I am not sure what the issue is as the input folder has complete privileges for read/write.

Hi, In the Options Tree, I have been changing the MIP Relative Optimality Tolerance to 0.5%, 1.0%, 5.0% and 10.0% to analyse the performance of the solution, gap and solving time. I wish to change the gap to 0.5%, 1.0%, 5.0% and 10.0% to analyse whether the solving time can be reduce by changing the gap. However, the CPLEX always stop at either 0.04%, 0.12% or 0.00% of gap. Is there any way to stop the CPLEX at 10% of gap?

When I want to use the modulo function in my linear model, I get the following error: “Constraint programming constraints cannot be used in combination with real valued variables, only with integer valued variables, element valued variables and activities.”. In my constraint I calculate the modulo of (x_{zht}*(t-1), Z) where Z is a parameter and I have used the function Ord to calculate the first part of the modulo, so x_{zht}*(Ord(t)-1). Also, I have tried making the indices a subset of Integers and label it as numeric, but then the model does not give any solution anymore (even when I turn the modulo constraint off). How can I make the constraints containing the modulo function in my linear model work?

Dear community, When I try to solve the attached model, I get the following errors: Warning: The columns "TransportToCustomer(Warehouse1,Customer5,038.001,1)" and "TransportToCustomer(Warehouse1,Customer399,038.001,1)" are equal in the generated mathematical program "LeastCostPlan". This may lead to non-unique solutions. For more information regarding potential causes and consequences, see the help associated with the option "Warning_duplicate_column". Warning: Only 3 out of 11565909 duplicate column warnings were reported. See also option limit_reported_duplicate_column_row_warnings. Warning: After zero iterations CPLEX 12.7.1 concluded that an integer solution to LeastCostPlan does not exist. Firstly, I don't really what this error means. In the example above, the shipping of product 038.001 to Customer5 on Period 1 and the shipping of product 038.001 to customer 399 on Period 1 do not have anything to do with each othe

Dear community,I just rolled into AIMMS, so the application is very new to me.I came across a problem with implementing constraints into my model. You can see the specific constraint and my model in the attached illustrations. After filling in the definition for the constraint, an error popped up, saying "The scope of index "cred" has not been specified.", where "cred" is the index domain for the variable "CarbonCredits".I already tried to re-implement the whole model, change the index and i messed around with different brackets in different positions. Nonetheless, i kept getting the same error.I would appreciate it if someone could help me out. A picture (of an example) on how the definition of this constraint should look like would be phenomenal as well.Thanks in advance, Stijn

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. 

Dear, I want to do a cycle for. I have two boundary values and I want to consider values between these boundaries. Then for these considered values I want to solve the Min_Total_Costs and have the values of Total Costs for the considered values. How can I write this cycle for? How can define set, ect? For now I wrote this code for e| (epsilon_e(e))>epsilonl and (epsilon_e(e)) CO2_ec:=epsilon_e(e); solve Min_Total_Costs; Total_Costs_e(e):=Total_Costs; endfor; with e the index of a set ep and epsilon_e(e) an integer variable. But it seems that it is not working. Can you help me? Thanks.

Hi. I tried to follow the tutorial to read the data from excel. I have manually inserted the data for the sets of the index c,t and r in AIMMS. Then, I must set a 3-dimensional parameter, e.g. waste(c,t,r) as shown in the picture below. I wish to insert the data for the parameter by using the axll function in AIMMS.        I put the excel sheet in the AMMS data folder. I tried using this coding:   WorkBookName := "roomWaste.xlsx"; if axll::WorkBookIsOpen(WorkBookName) then          axll::SelectWorkBook(WorkBookName); else          axll::OpenWorkBook(WorkBookName); endif; axll::SelectSheet(SheetName : "Waste"); axll::Read

Hello Team, I am working on the multidepot-VRP problem an extension of your practical example capacitated VRP. I want to make a model in which vehicles will depart from their depots to serve different customers and turn back to the same depot where it started from. I made a rough model but facing some sort of errors. Kindly check and help me to resolve my model. I shall be really thankful to you. Looking forward for your kind response. Regards

Dear Community, I plan to work from the Python workbench to call AIMMS to execute the optimization for my research project. I have some questions about linking AIMMS to Python: 1) How do I execute the AIMMS file by calling it from Python? 2) Will the results be written back to Python? Or, how can I export the results to the Python workbench? Thanks in advance, I look forward to executing my research with AIMMS... Best regards,

Hello everyone the following constraint       0<= P_cotw <= sum PMAX_c 'tau' w 'tau<=t How can I declare the right side of the restriction   c, o, t, w subscripts. 'tau' t = {1,2}   My case is: Constraint LimProdCan {     IndexDomain: (c,o,t,s);     Definition: PotGenCan(c,o,t,s)<=CapConstruir(c,t,s); }   Thank you

The AimmsXLLibrary was introduced in AIMMS 4.20. You can deploy your AIMMS project to more platforms with less restrictions, because this library can communicate with Excel files in server environments where Excel is not installed. For instance, while running AIMMS through a WebUI on PRO or on Linux. The AimmsXLLibrary doesn’t require Excel to be installed in order to read from or write to an Excel (.xls/.xlsx) file. You first need to add the system library `AIMMSXLLibrary` to your model, and then you can use the predefined `axll::` functions. Read more...

Dear all, I have a constraint in AIMMS which is as follows: lambda1(q)*0+lambda2(q)*mu1+lambda3(q)*mu2+lambda4(q)= 1/T(q)*sum[k,sum[l,i(k,l,q)*min(travelTimes(k,l),tau)]]|k in LocationOnRouteQ(q) and l in LocationOnRouteQAfterK(k,q) The problem is in this part: k in LocationOnRouteQ(q) and l in LocationOnRouteQAfterK(k,q) Because I get an error that the scope of index k has not been specified. However, when I put the indices k and l in the index domain I get the error that the scope already has been specified. I want to let the k come out of the set LocationOnRouteQ(q) and l out of subset LocationOnRouteQAfterK(k,q) and I have tried many things, but none worked out. LocationOnRouteQ(q) and LocationOnRouteQAfterK(k,q) are both subsets of the set Locations and I got k and l as indices in the set Location. I hope someone can help me. Kind regards, Aimée

I have a parameter over weeks with historic and forecast info. I want the historical week to be a dotted line and from the current week onwards a solid line. I use an annotation ‘dash’ and created a string parameter that have dash for the historic weeks. I added this as annotation the parameter, but if I use this all the weeks are dotted. (When I remove the annotation the whole is solid, as it should be). So is it possible to change the line over the axis?

Dear all, I have a few questions about my model, which I hope the AIMMS community can answer. Please bear with me, as I should be drawing to the conclusion of my thesis (when this model works). Sum and indices In the accompanied model, I am trying to add several constraints. However, when setting these constraints I often encounter errors like "the index (p) does not denote a subset of the domain of set "FactoryLines"" for instance. I often find that I make mistakes with the indices in the constraint itself and within the constraint definition. I have tried looking at the guides online, but with no effect. Could anyone explain to me (preferably in layman's terms) how the indices in constraints work as well as indices within a sum argument? I am encountering similar problems with the parameters "IncomingStock" and "OutgoingStock" Stock balancing One of the decision variables, StockAtWarehouse is made from t

Hi there, I have a 3-dimension binary variable as my parameter, which indicating what combination of items are in a paticular batch of order as below (the example shows I have item 1,2,0 in my Bathch-1).  My question is that, if I have 1000 batches, is it possible to directly input this data from excel? I know the answer is probably yes with the Spreadsheet:: functions, but I’m a little bit confused how should I arrange my data in excel? Should I include the data of one batch in one spreadsheet and read the entire excel file use Spreadsheet::RetrieveTable? If this is the way, what should I do when I have a variable of 4 dimensions? And another (dummy) question-if I need to use the code to retrive data from excel, which section should I put this code in? MainExecution? Thanks in advance!

Hello,I am trying to use database procedure function to extract some data from a HANA view database.Unfortunately, table name has dots (“.”), so it seems like AIMMS cannot parse it for SQL query properly. For example, the table name is something like xx.yy.zz/pp, where you can see some dots between xx, yy, and zz.  Can you help us to figure out proper syntax to write sql query with this type of name?Thank you!  

I would like to know how to get the sensitivity analysis of a constraint shadow price. For example, say we have the following constraint: x+y ≤ c and its shadow price "SP". How do I get the relationship between c and SP ? In other words, the sensitivity analysis of SP according to c. I would appreciate if you can show me how to achieve this in AIMMS. Thank you very much for your assistance!

Hi, I would like to do a multiple optimization in AIMMS. For example I would concurrently minimize the costs and maximize the amount of captured carbon dioxide. How can I set this kind of optimization in AIMMS? Thanks. Best

Hi everyone!   Is there a way to change if I want to show or not the unit and the number of decimals by parameter?   Example:    My wish: 500     |     0.00%   Thanks.

Dear AIMMS Team, I am a PhD student in the UK and I have been trying to solve a non-linear non-convex optimisation problem with different solvers for a Journal Paper. The following are the CPU details: Intel Core i7 2.2GHz, 16GB RAM memory, 64-bit operating system. So far the solvers CONOPT 4.0 and IPOPT 3.11 have been able to solve the case without problems. Unfortunately, when I use MINOS the following error appears: Errors/Warnings Warning: Model status 13: Error no solution, Solver status 9: Error: Setup failure (see message window). Message Window For the MinCost 39239 columns have been generated of which only 31245 are non-empty. Calling MINOS for NLP of 34726 rows, 31245 columns and 109867 non-zeros. Calling MINOS to solve NLP model 'MinCost' and minimize GenCost. Generation required 0.406 seconds. MINOS error: Not eno

Hi! We were able to execute the model already but we're having warnings that the result for this column is similar with the other column. Take for example the constraints 22 and 26? How do we code the "summation"? Sorry I'm just a beginner and I have no one to teach me and I only have a month to study everything because the deadline is just for 2 months. Our model in AIMMS can be downloaded here: https://drive.google.com/open?id=1pUgymOpS0-oJLxc_IU6tjt7YEiKkHqmW

hi all, need help for linearizing step function. say "y" is depending on "x" such that, y= ax if x is between 1 and 2 y= bx if x is between 3 and 4 y= cx if x is between 5 and 6 a, b and c are parameters/constant which will have values 8 or 9. "y" is not final objective function and a, b and c must choose value either 8 or 9. solution requested for maximizing/minimizing "y". thanks.