Originally posted by: AnushKara

Hello everyone,

I am a beginner in using CPLEX optimization studio. I want to formulate the Resource-Constrained Project Scheduling Problem (RCPSP) as a mixed integer linear optimization problem by implementing the Discrete-Time Formulations Based on "Pulse" Start Variables in the aggregated and the disaggregated version. I have excel data containing 48 instances (sheets), each containing 30 activities. Here my excel structure(attached a small screenshot of the sheet outlook):

- 32 is number of activities (including dummy start and finish activities)

- 4 is number of resources

- 24,23,25,33 are capacities for each resource

- the lines above with the following order: duration of activity; the requirement of resources 1,2,3,4 respectively for the activity; the number of direct successors for the activity; activity IDs of all successors for the activity under consideration. 

I am attaching my model and data file. In the data file you can see that I worked on some instances manually inputted and the model works fine for those instances. However, as I mentioned above, I have a problem retrieving all the instances from excel sheets and running them simultaneously.  I hope you can help me with this issue and thank you very much in advance for the consideration and help. 

Kind regards,

Anush

Hi,

have you looked at the example I gave at https://www.ibm.com/developerworks/community/forums/html/topic?id=b3e7bd19-e135-4431-b815-8166cc25e660&ps=25 ?

regards

Originally posted by: AnushKara

Hi,

Thank you very much. I followed the zoo example. My model works now but only for one instance. And actually I worked the zoo example and I only get the result of one objective as it also runs for one instance/sheet (with number of Kids = 300). So, could you please look at the code which I downloaded for the zoo example and tell what is wrong so that from this zoo example I can update my model as well. Thank you very much in advance.

Moreover, 

I want to extract the results to my excel sheet. And I also need solving time information. Here is the code I am using to get the information.

float temp;
execute{
var before = new Date();
temp = before.getTime();
}
execute timeTermination {
cplex.tilim = 600;
}

execute{

var after = new Date();
writeln("Solving time ~= ",(after.getTime()-temp)/1000);
}
 

However, I need to extract it and use SheetWrite command and here is my try for it but it doesn't work:

Solving time to SheetWrite (ExcelData,"Results!C7"); -- I get error as there is no Solving time defined. 

Can you please help me with this as well?

Thanks a lot!

Anush

hi,

in the postprocess I added

float costResult;
float solvetime;

execute
{
writeln(results);
writeln("cost = ",cplex.getObjValue());
costResult=cplex.getObjValue();
solvetime=cplex.getSolvedTime();
}

and now I get

{<40 6> <30 2>}
cost = 3800
 {<40 7> <30 1>}
cost = 3900
 {<40 8> <30 0>}
cost = 4000

and I get that in the excel spreadsheet

regards

PS:

https://medium.com/@alexfleischer_84755/optimization-simply-do-more-with-less-zoo-buses-and-kids-66940178db6