Unable to convert from Stella

[ArsEN]

Hello,

I have been struggling to convert a project made in Stella to Vensim using the "stel2ven" conversion tool mentioned several times in this forum. The problem is that the tool kind of refuses to start, it just shows a black window for a second and then shuts down immediately. I am now unable to convert the project as I am unaware of any other way to do it. Any help would be very appreciated.





P.S. Sorry for my English as it is not my native tongue.

[Administrator]

Are you running it by double clicking from Windows Explorer?

The application is a command line tool. You will need to start a command prompt, change directory to where stel2ven.exe is and type stel2ven.

It might be easier to create a small batch file to do what you want. Try creating a file called ConvertModel.bat in the same directory as stel2ven.exe. Right click ConvertModel.bat and select "Edit". In the file, add the lines

Code: Select all

stel2ven.exe "<PATH TO STELLA MODEL>" "<PATH TO VENSIM MODEL>"
pause

Double click this new batch file and you should see it working.

Tony.

[ArsEN]

I tried doing what you suggested, but the command prompt says "unable to open the file", here is what my ModelConvert.bat looks like:

Code: Select all

stel2ven.exe "<C:\Models\ModelStella.stm>" "<C:\Models\ModelVensim.mdl>"
pause

stel2ven.exe aswell as ModelStella and ModelVensim are all placed in the same directory.

[Administrator]

Try

Code: Select all

stel2ven.exe "C:\Models\ModelStella.stm" "C:\Models\ModelVensim.mdl"
pause

[ArsEN]

Thank you, that helped. However, when I ran the conversion there were 2 errors in it - do those errors actually prevent the tool from completing the conversion or can I just correct them manually ? Because when I opened ModelVensim.mdl it was totally blank, with no equations in it, as if no conversion happened at all.

[Administrator]

What were the errors?

And can you try this instead (output a VMF instead of MDL).

Code: Select all

stel2ven.exe "C:\Models\ModelStella.stm" "C:\Models\ModelVensim.vmf"
pause

Depending on model size, it's often easier to just rebuild the model manually. That way you can be sure you have all the correct structure in place.

Tony.

[ArsEN]

Thank you once again for replying. Yeah, I have already tried to rebuild the model manually as it is a really small one but there is a little mistake that I am unable to get rid of. I would like the "porodnost" variable to be defined as a graph of "O2" using the Lookup ---> As Graph method. In other words, the "O2" is supposed to be on the x-axis and the "porodnost" on the y-axis. However, when I draw the graph manually and hit OK I get an error saying there is an unused input which was expected to be used (the O2). The thing is, I have no idea how to include the input. If you could please have a look at my project, it would be very appreciated. The project is written in my native language, I am very sorry about that.

[Administrator]

Rename "porodnost" to "porodnost F" (a function).

Now create a new variable called "porodnost". The equation for this should be
porodnost = porodnost F ( O2 )

[ArsEN]

I am very sorry but I am not sure I 100% understand what you mean, I tried what you suggested and now the equation in "porodnost" is expecting an operator.

[Administrator]

Try the attached.

[ArsEN]

Wow, many thanks, it is really working now !