BodePlot documentation error

The documentation for BodePlot lists FeedbackType as an option. It states that for BodePlot[lsys], lsys is wrapped in a feedback loop before plotting, with the default being negative feedback. When I read this I was horrified – Why would I want BodePlot with no feedback option to alter the model before plotting? In fact, why would I even want the option? If I want to plot the model with feedback, why not just use SystemsModelFeedbackConnect to construct the model I want to plot?

So I investigated. The result is that, while BodePlot does accept FeedbackType as an option, the output of BodePlot is always a plot of the model as given, with no feedback, independent of the value of FeedbackType. The attached notebook demonstrates this.

I think this is good. I suggest that the FeedbackType option for BodePlot be eliminated and references in the documentation be deleted.

Kind regards,
David

BodePlot FeedbackType TFM.nb (283 KB)

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Sorry I’m seeing this years later.

You are right that FeedbackType has no effect on the plot itself. But it does effect the StabilityMargins.

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