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Hi.I am trying to solve a large problem in parallel using asynchronous solver sessions. However, I get this error as soon as I start the simulation ‘The number of simultaneous solves by solver 'CPLEX' exceeds the license limit of 1.' I have CPLEX (Full) solver in AIMMS. Is this because I have a personal node locked AIMMS business license? How do I check the number of solver sessions that I can run simultaneously in AIMMS? Is there a way to activate the Parallel CPLEX option? Thanks.

Hi,  I am wondering if it is  possible to set a specific value for the best LP bound of  a  Mathematical program (before executing the Mathematical programof course)? Thanks

HI everyone, so I have to model a problem but when I run the procedure, it tells me: Warning: CPLEX: Q matrix is not positive semi-definite.Warning: Model status 13: Error no solution, Solver status 9: Error: Setup failure (see message window).I have no idea where my mistakes are, that's why I come to ask for your help.so here is my problem :I have 4 variables, X(j,i) and Q(i,l) are non negative and Y(i) and E(i) are binary variablesMy function to minimize is : sum( (j,i), csb(j,i)*X(j,i) ) + sum( (i,l), cbd(i,l)*Q(i,l) ) + sum( i, ce(i)*E(i) ) + sum( i, co(i)*Y(i) )My constraints are: sum(i, X(j,i)*Y(i)) <= capmp(j)sum(l, Q(i,l)) <= capb(i) + 50*E(i)sum(i, Q(i,l)) >= ed(l)8.333*(sum(j, X(j|j="Afyon",i))+sum(j, X(j|j="Konya",i))) + 9.091*sum(j, X(j| j="Import",i)) = sum(l, Q(i,l))sum(i, Y(i|i="Istanbul")) =1sum(i, Y(i|i="Ankara")) =1sum(i, Y(i|i="Izmir")) + sum(i, Y(i|i="Sakarya")) + sum(i, Y(i|i="Adana")) =1sum(i, E(i|i="Izmir")) + sum(i, E(i|i="Sakarya")) + sum(i, E(i|i="Ada

I wanted to know how is one supposed to take input from excel sheet when I publish my app on Cloud. I have tried uploading the excel sheet on cloud but I’m not sure how to locate the file on cloud and read data from that. Could you please guide me through this? Thanks.I have attached some screenshots for your reference.

Hi @Gertjan , We are really interested in using the Calendar widget in the WebUI. Is there any update on when will it be available?    Thanks, Cristina Sanchez Molero  

Hi,I want to read data for a parameter P(x,y) from excel file. The parameter is two dimensional.And the data lies in one of the sheet(say Demand) of a excel file(say DataFile). I have tried ReadList but it is not working as the range of x lies in  A2:A50 and the range of y lies in E2:E50 and data lies in T2:T50.Help me to read the data with out creating another sheet. 

Hi,how is it possible to obtain a worse outcome on a more powerful PC system? Are there solver options which are benefitial for a faster PC system?In my specific case, I run a Mathematical Program (MIP) minimizing a target function. Since the computation effort is quite high, I introduce an Upper Bound to reduce the solution set. However, if I run the identical probelm instance on two systems, the more powerful one is not able to even calculate a Lower Bound. I use CPLEX 20.1. Any idea why this could be or how to configure solver options? Thanks and best regards 

Hi,I am dealing with the allocation problem where my result is a binary variable. In the application the result, the data filled in the variable, is presented in a nice way but I cannot get it to work in the WebUI. Is there a way to get this done ? When trying to display the binary variable in a table in the WebUI, no data is shown. Kind regards,Marie

I’m using CSVProvider 1.1.1.2 for writing outputs to CSV.  While writing, certain rows are missing in the csv file where the variable values were 0.  When checking in AIMMS (right click variable → Data) I see the domain still has that index but empty value (which means it is 0).  However, while writing to CSV the index where variable values were 0 is missing.  Is it possible to either include a blank row or with values 0 for the index position where the variables were 0 ?

Is there a way to lock a page in Web-UI with a password?

I’m trying to define a limit to RAM memory available to solve a generated mathematical program. Is this function related to this? I tried code below, but it’s stoping my solve before the time_limit defined, before the the GAP defined and also is not using 24 GB available. And before I changed the code to use gmp functions it was taking more than 11 GB.   

Can AIMMS  interface  Python，such as tensorflow？

Hi,I want to build a model that can transport stuff from (i to j) directly or by stopping over at facility r.The transportcost (i to r) and (r to j) are cheaper than the direct transport (i to j). Problems:Open(r ) is either 0 or all possible r are opened and the amount is divided up evenlyEven if transportcosts are way lower for the extrastop r than without, the model does never choose to move all products past extrastop r. (capacities are more than enough)  (goal is to minimize total cost (fixed cost and transport cost included)Related Constraints:Amount(i,r)+Amount(d,r)<=Demand(i)*OpenRecycling( r) // index (i,d,r) sum(i,Amount(i,r))+sum(d,Amount(d,r))<=Capacity(r)* Open( r)   //index (r ) sum(r,Amount(i,r))+sum(r,Amount(d,r))=(Returnrate(i)*(demand(i))) //index (i,r) sum(i,Amount(i,d))<=Capacity(d)*open(d)      //index(d) sum(i,Amount(i,d))=sum(r,Amount(d,r))         //index(d)  Thanks for your help.I´m more than happy to post my model if that helps

I have a String parameter for BeginDateofCalendar which takes a string of date.I created a procedure for getting value for the above string parameter using DialogGetDate which gives me option to select a date from Calendar.But it only working in WinUI. When i am running the procedure in a page in WebUI its running but the calendar is opening in AIMMS App, not in WebUI.what should i do so that the calendar opens in WebUI and not in AIMMS App?

Hello, for a submission I just had to download AIMMS. I have applied for the Academic License to use it. After I received the verification mail, I proceeded exactly as described in the mail. However, I still can't really use AIMMS because I always get the following error message when creating a new project. As soon as I want to open another project, I also get an error message. When I want to implement a new model I can't add new sets, parameters etc. either. Any help is highly appreciated! 

I have a Binary Variable X(C,V,T).Suppose for  t  and v  , X(c,v,t) is 1 for a c1  in C.I have another element parameter/variable (Range in C) F(V,T).now using this variable X how can i find F(v,t) = c1    

Hi, I these days, I realized a new limitation with the new academic license delivery. Before, I was able to run two instances of AIMMS at the same time. However, now I can only run one instance at a time. Here are my two main uses for parallel instances of AIMMS:I am dealing with a quite heavy energy system model that runs around 2 to 20 hours (depending on the level of details). Sometimes I need to run several scenarios for a specific sensitivity analysis. It would be very useful for me if I can run the model on several computers at the same time. Sometimes I want to continue coding in AIMMS while it is running a problem.  Would it be possible to run two or more instances of the model at the same time for academia? 

I looked into the example of the dex:: library and I tried the DataExchange example. However I still have trouble to get started in my own program. I want to read a JSON file like given in the attachment and use the data in some variables in my AIMMS program. Could someone help me with a simple example program?

Hi, I used to watch two aimms videos, one of them was about performance tunning of problens and the other was about infeasibility of models, but after the chanegs in the site I cannot find then anywhere. Doesn anyone remember of these videos and where to find them?

Hi everybody, I am trying to convert the unit power [MW] into the unit energy [MWh] considerung the specific time duration per timestamp [h] or [qh]. Has anyone an idea how to solve that?

I want to write data in Excel. Generally “Spreadsheet::Assign...” commands work fine. However, I fail to include zeros in the output in Excel. I want this:i/t 1 2 1 0 0 2 5 7  I get this:i/t 1 2 2 5 7  Now I found the “axll::”  library and the axll::WriteTable command, which seemed promising. Unfortunately this seems to work differently, since commands need an open workbook, which the “spreadsheet::” commands don´t. Combining both worlds doens´t work either.  Can someone help? I am very confused. Thanks

Dear All,I want to write an equation for calculating growth in a parameter or variable. As an example:Pop(t) = Pop(t-1) + GrowthFactor(t)*Pop(t-1)How to do this inside AIMMS?Thank you.

Looking at screenshots can anyone tell me why the element parameter Calc(i,t) is not getting calculated? The problem comes when I am using ‘shift’ unit of measurement. If I use standard units like day or hour, the element parameter gives correct answer.I need the data of element parameter to be as follows: For example for t=2021-03-01 00:00 answer for b1: 2021-02-01 08:00 (since we are deducting 2 shifts) and for b2: 2021-02-01 00:00 

I want to get registry value to check for dll registration.Is is possible in AIMMS?Please help me.

Hi,I am working on a project of delivery planning.In my model i have a constraint which defines the Unavailability of a vehicle for some time due to maintenance or already on a delivery. The Time a vehicle becomes unavailable is a parameter.the constraint is :Here,X_v,t → indicator variable for maintenance(whether need to go for maintenance)S(v) → time required for maintenance of vehicle v status_v,t → indicator variable for availability of vehicle v on day t   I am unable to write it in AIMMS. how to get the range of tau ?i was able to get the range for a single value parameter h using SubRange function                             tau in SubRange(T, t, t + h)but for a parameter set S SubRange is not working. Writing S(v) in place of single valued parameter h giving me  this error*There is a mismatch in the master sets of set "T" and domain set "S" in the first argument of the call to intrinsic function "SubRange". what could be a possible solution for writing this constraint if S(v) i