This is machine translation

Translated by Microsoft
Mouseover text to see original. Click the button below to return to the English verison of the page.

Note: This page has been translated by MathWorks. Please click here
To view all translated materals including this page, select Japan from the country navigator on the bottom of this page.


Rational expression in a rootlocus plot

MuPAD® notebooks are not recommended. Use MATLAB® live scripts instead.

MATLAB live scripts support most MuPAD functionality, though there are some differences. For more information, see Convert MuPAD Notebooks to MATLAB Live Scripts.

Value Summary

MandatoryMuPAD® expression

Graphics Primitives

ObjectsRationalExpression Default Values


RationalExpression is the internal name of the expression whose roots are depicted by plot::Rootlocus.

A rootlocus plot depicts the roots of a rational function p(z, u) in the complex plane, depending on a parameter u. The expression p(z, u) is stored as the attribute RationalExpression in the rootlocus object.

Usually, a user will have no need to access the attribute RationalExpression, since it is set by plot::Rootlocus directly.


Example 1

We define a rootlocus plot:

r:= plot::Rootlocus(z^2 - 2*u*z + 0.81, u = -1..1):

The function z2 - 2 uz + 0.81 is stored as the attribute r::RationalExpression in the object r:


We can redefine this attribute:

r::RationalExpression:= z^3 - 2*u*z + 0.81:

Was this topic helpful?