showConfidence(plot_handle) displays
the confidence region on the response plot, with handle plot_handle,
for an identified model.

showConfidence(plot_handle,sd) displays
the confidence region for sd standard deviations.

Input Arguments

plot_handle

Response plot handle.

plot_handle is the handle for the response
plot of an identified model on which the confidence region is displayed.
It is obtained as an output of one of the following plot commands: bodeplot, stepplot, impulseplot, nyquistplot,
or iopzplot.

sd

Standard deviation of the confidence region. A common choice
is 3 standard deviations, which gives 99.7% significance.

z1 is an iddata object that contains time domain system response data. sys is an idpoly model containing the identified polynomial model. h is the plot handle for the bode response plot of sys.

Show the confidence bounds for sys.

showConfidence(h);

This plot depicts the confidence region for 1 standard deviation.

z1 is an iddata object that contains time domain system response data. sys is an idpoly model containing the identified polynomial model. h is the plot handle for the bode response plot of sys.

Show the confidence bounds for sys using 2 standard deviations.

sd = 2;
showConfidence(h,sd);

sd specifies the number of standard deviations for the confidence region displayed on the plot.

Alternatives

You can interactively turn on the confidence region display
on a response plot. Right-click the response plot, and select Characteristics > Confidence
Region.