AIMMS Language

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.

CSV files are a de facto standard for communication of data. AIMMS provides the libraries code:DataLink and code:CSVProvider for the serializing of CSV files. In this article an example is provided for reading data from a CSV file.

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 am trying to open the model that gives the demo of how to connect AIMMS with Python in AIMMS Developer, however I am getting an error and I am not able to open the model. The model given at the below link:https://how-to.aimms.com/Articles/487/487-aimms-with-python.html 

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

If I have a variable where row A is timeline with index t and B are calculated values, how to calculate Non-zero Average of Values in B?A 1 2 3 4 5 B 4 0 6 0 7

I want visualize stock levels with their respective safety stock level. I have 2 parameters running over products and weeks. See below. The bar is good, but the lines are connected insead of different per product.   Is there a way to fix this?

 I have large a planning problem in AIMMS, which is linear optimization. I am using GUROBI 9.0 for solving it and the solver is set to use the Barrier method based on our experience that Barrier converges faster than Simplex in our large-scale problem. After around 56 hours, the program stopped and I got the “Warning: Model status 13: Error no solution, solver status 1: Normal Completion”.Here are screenshots from the warning and progress panels of AIMMS.  Error/Warnings PanelProgress Panel​​​​​None of the existing questions and discussions on “Warning: Model status 13” are related to the case that it says “Solver status 1: Normal Completion”. I could not find any more information on software or the AIMMS manual regarding this issue. I need to find what is the source of this problem. I would be grateful if you can help me with this issue.Thanks,

hi all,sorry for the trivial question but was trying to figure out:how to force aimms to show “0” values for parameters and variables/results and correspondingly exporting those parameters to excel with “0”at the moment, whenever the parameter or variable has “0” is appears as empty line/cell.any hints on these two questions much appreciated!thanksnick

Good morning.I am converting our proyects in AIMMS from version 3 to version 4 and the DSN that already was used to connect to Access has failed. I used the extension (*.mdb), also tried with  (*.accdb) but doesn´t work. Could you help?Thanks a lot

I am trying to replicate the Softdrink Planning Tutorial, however it requires declaration of a  Compound Set. I have gone through the document:https://how-to.aimms.com/Articles/109/109-convert-compound-sets.htmlHowever, I am unclear how to convert the Compound Set given in tutorial. Could you please guide me through how to convert this particular set with set mapping. Thanks.  Set PlanningGanttChartRows {    SubsetOf : (Factories, ProductionLines);    Index : r;    Definition : {        { (f,p) | p in FactoryProductionLines(f) }    }}Set PlanningGanttChartBarTypes {    Index : b;    Definition : data { ’In Use’, ’In Maintenance’ };}ElementParameter PlanningGanttChartStartingWeek {    IndexDomain : w;    Range : Weeks;    Definition : w;}Parameter PlanningGanttChartDuration {    IndexDomain : (r,w,b);}

I am a beginner to AIMMS and was trying to create the Softdrink Planning model by following the procedures in AIMMS_tutorial_professional.pdf. However, I was stunk at specifying the table name attribute step in tutorial page 77/217. Whenever I click the “Table name” wizard, a window will pop up saying “Error opening datasource data\\Softdrink Planning.dsn make sure this is a valid datasource”. Anyone knows how to solve this issue? Your help would be highly appreciated!I also tried to click the “Table name” wizard in the completed project model but I still have same issue.

While calculating a Sum-Function  I encountered a problem  (see error message below):While using the power of X=1 and X=2 the model works perfectly however with any other number (also negative numbers) it displays the error below in red.Function: Sum[p, 2 * (L1(p)+0.001)^(X) ] Using +0.001 to avoid any division by 0 (in case of X being negative).L1(p) being a variable which is defined by a constraint L_1(p):Sum[i,L(p,i)] + L1(p-1)= L1(p)And L(p,i) in the constraint being a binary parameter. To run AOA the name of the AOA callback procedure should be assigned to suffix 'CallbackAOA' of 'Loesung'. For example: Loesung.CallbackAOA := 'OuterApprox::BasicAlgorithm'; where 'OuterApprox' is the prefix of the Outer Approximation module.Warning: Model status 13: Error no solution, Solver status 10: Error: Solver failure (see message window).Thank your for any help.  

I am getiing an error :The undeclared "1" is not an index. I am on the declaring identifiers portion of the course building my 1st AIMMS app.

I have a variable of a MIP problem, for example: total_power_plants = 2.7 but I only want to use the integer part of this value, that is 2, I have been reading this article but it does not work nor is it what we need (https://how-to.aimms.com/Articles/199/199-model-rounded-variable.html#example). Could you bring me some solution, please?

While solving a LP, I ran into the following error.  Below some snapshot from the message window.  100   9.7583200e+09   9.7583173e+09  3.89e+00  1.71e-01  1.34e-05  2.65e+03 101   9.7583195e+09   9.7583194e+09  5.20e+00  6.76e-03  6.16e-06  6.06e+04 102   9.7583195e+09   9.7583195e+09  1.78e+01  1.72e-04  2.39e-06  3.28e+06Barrier time = 767.38 sec. (945691.46 ticks)Parallel mode: deterministic, using up to 4 threads for concurrent optimization: * Starting dual Simplex on 1 thread... * Starting primal Simplex on 1 thread...Dual simplex solved model.Compressing row and column files.Advanced basis not built.Total crossover time = 300.28 sec. (132581.11 ticks)Total time on 4 threads = 1136.34 sec. (1101932.44 ticks)Memory in use by CPLEX 12.10.0.0: 8662892544 bytes.There is 8.26e+03 Mb in use by CPLEX 12.10.Warning: Model status 13: Error no solution, Solver status 10: Error: Solver failure.I am wondering if dual simplex solved the model, why there is error no solution?Any ideas to troub

A very basic question from a new user:I am trying to get started in the foundational training. When I create a new project to follow the basic tutorials, I am unable to create a new variable (though I can create sets and parameters). There is no error message that appears, but the buttons are grayed out (see screenshot below). I have tried in several AIMMS versions. Can anyone tell me what's going wrong here?

I want to write a function in AIMMS which should return a value or an element of Set X(say).The function is say F(a,b,x) where a in A, b in B, and x in X. The function F should return an element(or value) x1 from set X if x1 is in X otherwise returns no value.for Example, say F(a,b,x) = x - 10 and X = {x | 0<= x <= 100}F(a,b,20) should return 10  and F(a,b,8) returns no value or a default value which AIMMS will not consider when using this functions return value in a constraint.

I’m trying to see the nominal coefficients property for a variable. I have CoefficientRange property selected and my  Calculate Sensitivity Ranges is ON. However, it doesn’t show the property when the problem is solved with AIMMS Linear Presolve being OFF? Please advise. Here’s the documentation I found:.NominalCoefficient Definition: When the property CoefficientRange of a variable is set and the option Calculate Sensitivity Ranges is not set to off a coefficient range sensitivity analysis is conducted such that the optimal basis remains constant. As a result of this analysis the variable suffix .NominalCoefficient contains the nominal objective coefficient value.

Dear staff,I would like to receive some help writing the following constraint for a mathematical model.Within a graph, I define arcs (i-j) where “i” and “j” are nodes. For each arc and node, I also have the following variables and parameters:p(i) binary variablep(j) binary variablea(i,j) continuous variableC(i,j) parameterH(i) parameterH(j) parameterI would like to write a constraint expressing the following conditions:if p(i) = 1 and p(j) = 0, then a(i,j) <= C(i,j)*H(j)if p(i) = 0 and p(j) = 1, then a(i,j) <= C(i,j)*H(i)if p(i) = 0 and p(j) = 0, then  a(i,j) <= C(i,j) * (H(i) + H(j))/2if p(i) = 1 and p(j) = 1, then a(i,j) <= C(i,j)If you have any suggestions on how to write the above conditions within a constraint, I will be glad.Thank you,