Importing Vensim Models

Upload a Vensim Model

Forio directly simulates Vensim models, using a special Vensim engine. Vensim is available from Ventana Systems, Inc..

In order to use a Vensim model, it must be saved in the VMF binary format (the file name will end in "vmf"). Other formats (such as "mdl" or "vpm") will not work.

Because the Vensim models are directly simulated and not translated, fidelity and performance are high. All mathematical expressions and functions are simulated exactly as in the desktop software. Model variables designated as "GAME" variables will be treated as standard Forio decisions. Model variables designated as "CONSTANT" variables and "LOOKUP" variables are decisions which may only be changed at the start of the simulation run. Models which use external resources such as spreadsheets, CSV or CIN files, custom DLLs, or databases will not simulate and may not be uploaded.

Here's how to upload your Vensim model.

  • Confirm that your Vensim model is a VMF binary format model. (e.g. it ends in .vmf). If the model is not a VMF model then open the model in Vensim, select File / Save As from the menubar, and choose "Binary Format Models".
  • In Simulate, click Browse... next to the upload field, select the model, and click OK.
  • If necessary, click the Next: Enter Forio Properties button.

After uploading the Vensim model, you will be prompted to enter Forio properties. This optional step allows you to specify number formats for Vensim variables. After that, you will be able to review the uploaded model.

Enter Forio Properties

NumberFormat
Sets a format for numbers, either as a model default or for individual variables. The format is similar to that of Excel, with a '#' indicating a optional digit, a '0' indicating a required digit, and a '%' indicating a percent.

M NumberFormat = #,##0
## sets a model wide default of zero decimal points (e.g. "1,000")

P Revenue.NumberFormat = $#,##0
## sets a number format for the variable revenue with the currency symbol (e.g. $1,000)

P Market Share.NumberFormat = 0.0%
## sets a number format for the variable market share with percent one decimal (e.g. .045 would be 4.5%)

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