This is machine translation

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

Note: This page has been translated by MathWorks. Click here to see
To view all translated materials including this page, select Country from the country navigator on the bottom of this page.

Introduction to Uncertain Elements

Uncertain elements (also called uncertain Control Design Blocks (Control System Toolbox)) are the building blocks used to form uncertain matrix objects and uncertain system objects. There are 5 types of uncertain elements:



Uncertain real parameter


Uncertain, linear, time-invariant dynamics


Uncertain complex parameter


Uncertain complex matrix


Uncertain dynamic system

All of the elements have properties, which are accessed through get and set methods. This get and set interface mimics the Control System Toolbox™ and MATLAB® Handle Graphics® behavior. For instance, get(a,'PropertyName') is the same as a.PropertyName, and set(b,'PropertyName',Value) is the same as b.PropertyName = value. Functionality also includes tab-completion and case-insensitive, partial name property matching.

For ureal, ucomplex and ucomplexm elements, the syntax is

p1 = ureal(name, NominalValue, Prop1, val1, Prop2, val2,...); 
p2 = ucomplex(name, NominalValue, Prop1, val1, Prop2, val2,...); 
p3 = ucomplexm(name, NominalValue, Prop1, val1, Prop2, val2,...); 

For ultidyn and udyn, the NominalValue is fixed, so the syntax is

p4 = ultidyn(name, ioSize,  Prop1, val1, Prop2, val2,...); 
p5 = udyn(name, ioSize,  Prop1, val1, Prop2, val2,...); 

For ureal, ultidyn, ucomplex and ucomplexm elements, the command usample will generate a random instance (i.e., not uncertain) of the element, within its modeled range. For example,


creates a random instance of the uncertain real parameter p1. With an integer argument, whole arrays of instances can be created. For instance


generates an array of 100 instances of the ultidyn object p4. See Generate Samples of Uncertain Systems to learn more about usample.

Related Topics