Chapter 2 Linear System Representation
Xmath Control Design Module 2-8 ni.com
Example 2-3 Using system( ) to Change the Attributes of an Existing System
sys4=system([0,1;-0.75,0],[1,0]',[0,1],[],
{dt=0.5});
sys4 = system(sys4, {inputNames = "Current",
outputNames = "Velocity",
stateNames = ["Torque","Angle"]})
sys4 (a state space system) =
A
0 1
-0.75 0
B
1
0
C
0 1
D
0
X0
0
0
State Names
-----------
Torque Angle
Input Names
-----------
Current
Output Names
------------
Velocity
System is discrete, sampling at 0.5 seconds.
abcd( )
[A,B,C,D,X0] = abcd(Sys)

The abcd( ) function extracts the component A, B, C, and D matrices

described in equations from a state-space system object as shown in the

State-Space System Models section. In addition, it returns the initial

conditions on the states if a fifth output argument is requested.

abcd( ) can be called on systems in either state-space or transfer function

form. If the system is a transfer function, the conversion to state-space is