# sdo.requirements.PhasePlaneEllipse class

**Package: **sdo.requirements

**Superclasses: **

Impose elliptic bound on phase plane trajectory of two signals

## Description

Use the `sdo.requirements.PhasePlaneEllipse`

object
to impose an elliptic bound on the phase plane trajectory of two signals
in a Simulink^{®} model. The phase plane trajectory is a plot of
the two signals against each other. You specify the radii, center,
and rotation of the bounding ellipse. You also specify whether you
require the trajectory of the two signals to lie inside or outside
the ellipse.

The following image shows the bounding ellipse and an example of the phase plane trajectory of two signals.

The X-Y plane is the phase plane defined by the two signals. *r _{x}* and

*r*are the radii of the bounding ellipse along the

_{y}*x*and

*y*axes, and

*θ*is the rotation of the ellipse about the center. The ellipse center is at (

_{R}*x*,

_{0}*y*). In the image, the phase plane trajectory of the signals lies within the bounding ellipse for all time-points

_{0}*t*to

_{1}*t*.

_{n}You can use the object as an input to your cost function,
and use the `evalRequirement`

command in the cost
function to evaluate whether your test signals satisfy the specified
requirement. You can then use the cost function and `sdo.optimize`

to perform parameter estimation
or response optimization, subject to the satisfaction of the specified
requirement. If you are performing sensitivity analysis, after you
generate parameter samples, you can use the cost function and `sdo.evaluate`

to evaluate the requirement
for each generated sample.

## Construction

creates an `requirement`

=
sdo.requirements.PhasePlaneEllipse`sdo.requirements.PhasePlaneEllipse`

requirement object and
assigns default values to its properties. Use dot notation to customize the
properties.

Use the `evalRequirement`

command to evaluate
whether test signals satisfy the specified requirement.

creates the requirement object with additional options specified by one or more
`requirement`

= sdo.requirements.PhasePlaneEllipse(`Name,Value`

)`Name,Value`

pair arguments. `Name`

is a property name and
`Value`

is the corresponding value. `Name`

must
appear inside single quotes (`''`

). You can specify several name-value
pair arguments in any order as `Name1,Value1,...,NameN,ValueN`

.

### Input Arguments

**Name-Value Arguments**

Specify optional pairs of arguments as
`Name1=Value1,...,NameN=ValueN`

, where `Name`

is
the argument name and `Value`

is the corresponding value.
Name-value arguments must appear after other arguments, but the order of the
pairs does not matter.

*
Before R2021a, use commas to separate each name and value, and enclose*
`Name`

*in quotes.*

Use `Name,Value`

arguments to specify properties of the
requirement object during object creation. For example, ```
requirement
= sdo.requirements.PhasePlaneEllipse('Type','>=')
```

creates
an `sdo.requirements.PhasePlaneEllipse`

object
and specifies the `Type`

property as an outer bound.

## Properties

## Methods

evalRequirement | Evaluate satisfaction of elliptical bound on phase plane trajectory of two signals |

## Copy Semantics

Handle. To learn how handle classes affect copy operations, see Copying Objects.

## Examples

## Version History

**Introduced in R2016b**