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Discrete FIR filter

This example implements a sinusoid filtering model and a comparison of FIR filter operation in MATLAB and Engee.
The Discrete FIR Filter unit independently filters each channel of the input signal with a preset digital FIR filter.

To implement filtering, we use the standard settings of the Discrete FIR Filter block.

image.png The Engee model
img.png The Simulink model
In [ ]: 
Pkg.add(["Statistics", "CSV"])

   Resolving package versions...
  No Changes to `~/.project/Project.toml`
  No Changes to `~/.project/Manifest.toml`
In [ ]: 
using Plots
using MATLAB
using CSV
using DataFrames
using Statistics

demoroot = @__DIR__

mat"start_simulink"
mat"p = genpath($demoroot); addpath(p);"
mat"p = genpath('/user/start/examples/helper_units'); addpath(p);"

Launching the Engee model

Let's look at the simulation results in Engee:

In [ ]: 
# Launching the model
modelName = "FIR"
PID_model = modelName in [m.name for m in engee.get_all_models()] ? engee.open( modelName ) : engee.load( "$demoroot/$(modelName).engee");

results = engee.run( PID_model )
Out[0]:
SimulationResult(
    "FIR_Out" => WorkspaceArray{Float64}("FIR/FIR_Out")
,
    "FIR_In" => WorkspaceArray{Float64}("FIR/FIR_In")

)
In [ ]: 
# Simulation results
FIR_In_x = results["FIR_In"].time;
FIR_In_y = results["FIR_In"].value;
FIR_Out_x = results["FIR_Out"].time;
FIR_Out_y = results["FIR_Out"].value;
In [ ]: 
# Plotting graphs
plot(FIR_Out_x , FIR_Out_y, legend = false)
plot!(FIR_In_x , FIR_In_y, legend = false)
plot!(title = "Simulation results in Engee", ylabel = "Data", xlabel="Time, c")
Out[0]:

Launching the Simulink model

Let's compare the simulation results in Engee and Simulink. To do this, we will first run a simulation of the model.

In [ ]: 
mat"""run_test_model('FIR')""";

Let's look at the results in Simulink:

In [ ]: 
# Reading model outputs
x1 = mat"In.Data";
x2 = mat"Out.Data";
y = mat"Out.Time";
In [ ]: 
# Plotting graphs
plot(y, x2, legend = false)
plot!(y, x1, legend = false)  
plot!(title = "Simulation results in Simulink", ylabel = "Response", xlabel="Time, c")
Out[0]:

Now let's plot the overlap of the output data Simulink and Engee.

In [ ]: 
plot(y, x2, legend = false) # Simulink
plot!(FIR_Out_x , FIR_Out_y, legend = false) # Engee
Out[0]:

As we can see from the graphs above, the models work the same way.

Conclusion

As a result of developing this example, we implemented a FIR filter, and also compared the capabilities of Engee regarding modeling in Simulink and showed the possibilities of connecting the MATLAB core to solve problems inside the Engee development environment.

Blocks used in example