# nyquistplot

Nyquist plot with additional plot customization options

## Syntax

## Description

`nyquistplot`

lets you plot the Nyquist diagram of a dynamic
system model with a broader range of plot customization options than
`nyquist`

. You can use `nyquistplot`

to obtain the plot
handle and use it to customize the plot, such as modify the axes labels, limits and units. You
can also use `nyquistplot`

to draw a Nyquist diagram on an existing set of
axes represented by an axes handle. To customize an existing Nyquist plot using the plot
handle:

Obtain the plot handle

Use

`getoptions`

to obtain the option setUpdate the plot using

`setoptions`

to modify the required options

For more information, see Customizing Response Plots from the Command Line (Control System Toolbox). To create Nyquist plots with default options or to
extract the standard deviation, real and imaginary parts of the frequency response data, use
`nyquist`

.

plots the Nyquist plot of the dynamic system
model
`h`

= nyquistplot(`sys`

)`sys`

and returns the plot handle `h`

to the plot. You
can use this handle `h`

to customize the plot with the `getoptions`

and `setoptions`

commands. If `sys`

is a multi-input,
multi-output (MIMO) model, then `nyquistplot`

produces a grid of Nyquist
plots, each plot displaying the frequency response of one I/O pair.

plots Nyquist diagram for frequencies specified by the frequencies in
`h`

= nyquistplot(___,`w`

)`w`

.

If

`w`

is a cell array of the form`{wmin,wmax}`

, then`nyquistplot`

plots the Nyquist diagram at frequencies ranging between`wmin`

and`wmax`

.If

`w`

is a vector of frequencies, then`nyquistplot`

plots the Nyquist diagram at each specified frequency.

You can use `w`

with any of the input-argument combinations in
previous syntaxes.

See `logspace`

to generate logarithmically spaced
frequency vectors.

plots the Nyquist plot with the options set specified in `h`

= nyquistplot(___,`plotoptions`

)`plotoptions`

.
You can use these options to customize the Nyquist plot appearance using the command line.
Settings you specify in `plotoptions`

overrides the preference settings
in the MATLAB^{®} session in which you run `nyquistplot`

. Therefore, this
syntax is useful when you want to write a script to generate multiple plots that look the
same regardless of the local preferences.

## Examples

## Input Arguments

## Output Arguments

## Tips

There are two zoom options available from the right-click menu that apply specifically to Nyquist plots:

**Full View**— Clips unbounded branches of the Nyquist plot, but still includes the critical point (–1, 0).**Zoom on (-1,0)**— Zooms around the critical point (–1,0). To access critical-point zoom programmatically, use the`zoomcp`

command. See Zoom on Critical Point.

To activate data markers that display the real and imaginary values at a given frequency, click anywhere on the curve. The following figure shows a Nyquist plot with a data marker.

## Version History

**Introduced in R2012a**

## See Also

`getoptions`

| `nyquist`

| `setoptions`

| `showConfidence`

| `nyquistoptions`

### Topics

- Customizing Response Plots from the Command Line (Control System Toolbox)