Misc

Misc

Simulator defaults

Starting a new simulation

Starting a new simulation will start a Grey-Scott simulation with two variables, $u$ and $v$.

Changing the default variable names

When changing “# variables” to a higher number than the variables names previously provided cover, any additional variables will be named by default to VARIABLE2, VARIABLE3, …, VARIABLE8 (whichever position they fall in), regardless of how many variables there are in total.

You are advised to change them to $v$, $w$, $q$ (for up to 4 variables) for simplicity, as other parameters are also defined according to them, e.g. $D_{VARIABLE2} = D_v$ and so on. variables beyond the fourth have no natural single-letter name; a common convention is u5 through u8, though any valid name works.

Default timestepping

By default, VisualPDE uses the Forward Euler method with $\Delta t = 0.1$, this is likely to be too big for many problems. We recommend reducing the timestep and/or changing the method in this case.

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