Introduction

SyntheSim is a way to simulate models in Vensim PLE with considerable interactivity. Changes made to the model while in this mode will cause the model to be re-run automatically.

To enter SyntheSim mode, click on the SyntheSim button . Like the normal Run command, SyntheSim should only be used once a model is built, its equations are defined, and everything is ready for simulation.

When you first run a model with SyntheSim, you will notice several immediate changes:

• All constant-valued auxiliary variables turn into slider bars.
• The boxes around box variables turn into miniature graphs of that variable over time.
• The upper toolbar will change, adding some new buttons and hiding some old ones.
• Permanent Graphs and Sliders, placed in the build window with the Input/Output Object button will become active.

NOTICE: Models that are large or require significant amounts of computation should be used with care in SyntheSim mode. If it takes your machine fifteen minutes to run your simulation, you may not want to use SyntheSim freely with that particular model. Why not? Every time you make a change, the computer will take around fifteen minutes to re-compute the simulation.

There is an option that allows SyntheSim to be used with complex models. Go to Model and select Settings. Under the Sketch tab, check Suppress SyntheSim during slider moves (big models).