How to Analyze Data Using the advice Command
You can use the
advice command to analyze
time- or frequency- domain data before estimating a model. The resulting
report informs you about the possible need to preprocess the data
and identifies potential restrictions on the model accuracy. You should
use these recommendations in combination with plotting the data and
validating the models estimated from this data.
advice does not support frequency-response
Before applying the
advice command to your
data, you must have represented your data as an
For more information, see Representing Time- and Frequency-Domain Data Using iddata Objects.
If you are using the System Identification app, you must export
your data to the MATLAB® workspace before you can use the
on this data. For more information about exporting data, see Exporting Models from the App to the MATLAB Workspace.
Use the following syntax to get advice about an
For more information about the
advice reference page.
Advice provide guidance for these kinds of questions:
Does it make sense to remove constant offsets and linear trends from the data?
What are the excitation levels of the signals and how does this affects the model orders?
Is there an indication of output feedback in the data? When feedback is present in the system, only prediction-error methods work well for estimating closed-loop data.
Is there an indication of nonlinearity in the process that generated the data?