Control package

The control package is part of the Octave Forge project.

Function list

Linear System Representation

Chapter	Function	Implemented	File
Basic Models	tf	yes	@tf/tf.m
	zpk	yes	zpk.m
	ss	yes	@ss/ss.m
	frd	yes	@frd/frd.m
	pid	no
	pidstd	no
	pid2	no
	dss	yes	@lti/dss.m
	drss	no
	filt	yes	filt.m
	rss	no

Model Interconnection

Model Transformation

Linear Analysis

Control Design

Matrix Computations

Some very basic examples

PT1/low-pass filter step response

Code: Creating a transfer function and plotting its response

 T1=0.4;               # time constant
 P=tf([1], [T1 1])     # create transfer function model
 step(P,2)             # plot step response

 #add some common markers like the tangent line at the origin, which crosses lim(n->inf) f(t) at t=T1
 hold on
 plot ([0 T1],  [0 1],"g")
 plot ([T1 T1],  [0 1],"k")
 plot ([0 T1],  [1-1/e 1-1/e],"m")
 hold off

Try also bode(P)! (a first order low-pass filter has -3db magnitude at f=1/T1)