$\mathrm{with}\left(\mathrm{BlockImporter}\right)$

This is an example of a band pass filter.  This example contains an algebraic loop, and therefore will not execute in Simulink.

We import the model with the following command.  We need to specify the name of the model to import, as well as a MATLAB® script that initializes the variable names.

$\mathrm{datadir}≔\mathrm{BlockImporter}:-\mathrm{DataDirectory}\left(\right)\:$ 

$\mathrm{model1} ≔ \mathrm{Import}\left(''filterb''\,\mathrm{path}\=\mathrm{datadir}\, \mathrm{init}\=''filterb\_init''\,\mathrm{inplace}\right)\:$

Using the PrintSummary command, we can view the model that we have imported.

$\mathrm{PrintSummary}\left(\mathrm{model1}\right)$

We can now simplify the model to reduce the number of equations.

$\mathrm{smodel1} ≔ \mathrm{SimplifyModel}\left(\mathrm{model1}\right)\:$

$\mathrm{PrintSummary}\left(\mathrm{smodel1}\right)$

First we take the system and build a set of differential equations, and assign the result to the variable sys.

$\mathrm{sys1} ≔ \mathrm{BuildDE}\left(\mathrm{smodel1}\right)\:$

The following table illustrates the different components of the variable sys1.

Using the information in the variable sys, we construct a simulation procedure.

$\mathrm{sol1} ≔ \mathrm{dsolve}\left(\left[\mathrm{eval}\left(\mathrm{eval}\left(\mathrm{sys1}:-\mathrm{equations}\, \mathrm{sys1}:-\mathrm{sourceeqs}\right)\,\mathrm{sys1}:-\mathrm{parameters}\right)\left[\right]\, \mathrm{sys1}:-\mathrm{initialeqs}\left[\right]\right]\, \mathrm{numeric}\,\mathrm{interr}\=\mathrm{false}\right)$

Then we plot the simulation results.