GRADIENT MODEL  (Replaced this with Gradient, because Damped Spring model not made yet.)

This simple model shows system in which some currency is transferred from one stock to another in a manner that is dependent on some diffusion constant K

multiplied by the difference in concentration between the two stocks. Thus, this is ultimately a model of diffusion, and this formulation can be applied to many kinds

of natural phenomena.  We will demonstrate the use of this model, below.

When Launched:

Now, let us observe some different results based on a varying End Time:

End Time = 100.

End Time = 5.