ModelInitiationException error while creating interface for a large vensim model in free version of Epicenter

#1

I am trying to build the interface for a vensim model (approx 180 variables). While making the interface I am facing the following error. Suggest any resolution.

forio

#2

Hi —

Thanks for the note. We’re looking at your model. There’s appears to be a compatibility issue with the model and Epicenter, which is unusual. (usually Forio and Vensim have excellent compatibility as we actually run a version of the Vensim engine under the hood for Vensim models). We’re looking further into this.

WILL

1 Like
#3

Please let me know if you need the model file to resolve the issue

#4

Apologies, Will is out on vacation. I can pick this up tomorrow. I do not need a copy of the model as I can pull that from your project directly. If the cause of the problem is obvious I’ll coordinate a response with Geromel. If I need your help in reproducing the issue I or Geromel will reach out to coordinate that.

#5

Using the file from your model directory I get an error attempting to load that file in the vensim server. Assuming the file wasn’t broken in transfer to your project, and I think Will said he could load it in the vensim desktop application, I’d like to send that file to Ventana for their analysis and feedback. Do I have your permission to do that?

#6

Yes, please do. It will be helpful.

#7

Hi, I am writing to check if there is any update on the resolutions. Please let us know,

#8

Thanks for checking in! We’ve sent the model to Ventana for review and are waiting for a reply. I’ll check back in here with an update next week if we don’t hear from them sooner.

  • Rob
#9

Hi,

As a follow-up, we’ve received a response from Ventana with a solution.

There were some custom spellings that were added to the model that caused the problem. We have an updated version of your model that Ventana provided with those spellings removed. They also indicated that they will make changes to Vensim to check for this issue in the future.

I would like to send the updated model file by email. Please email me directly at rpratt@forio.com with the appropriate contact information.

Best,

Rob Pratt
rpratt@forio.com

#10

Hi, just checking back to see if the corrected model resolved your issues? Let us know if we can do anything else to help.

#11

Thanks for the support. We are able to create the dashboard now using the file Rob sent. I am also attaching the screenshot the text comparison of the major changes done in the file.

54%E2%80%AFPM
Screenshot 2026-03-04 at 12.30.54 PM.png2376×590 66.4 KB

left side is the original file and right side was sent by Rob.

Also, with the updated file while creating a input slide for a variable we are getting following error message. Can you help with that ?

Error: Index -1 out of bounds for length 0
https://forio.com/v2/run/tdsciitb/sd-varuna-river-rejuvenation/0000019cad9db5a512063d44be950066c298/variables/?include=“no. of hrs pump operated”
500: Internal Server Error
Type: java.lang.StringIndexOutOfBoundsException

#12

We have noticed one more thing while developing the dashboard. For some variables we had taken value 0.02 but when model load on dashboard it shows the values to be 0.019999999552965164. Attaching the screenshot as well.

20%E2%80%AFPM
Screenshot 2026-03-04 at 6.41.20 PM.png910×434 28.8 KB

#13

Hi – regarding the StringIndexOutOfBoundException – we think this might work if you remove the period from the variable “no. of hrs pump operated”. Does that help?

We’re reviewing this internally in the meantime to see why this happens.

Re the decimal places, I’ve responded to that in your other thread. You need to set the number format.

1 Like
#14

It worked. Thank you for the support.