ss2des

(polynomial) state-space to descriptor form

Calling Sequence

S=ss2des(Sl)
S=ss2des(Sl,flag)

Arguments

Sl syslin list:proper or improper linear system.

: :flag character string “withD” : :S list :

Description

Given the linear system in state-space representation Sl ( syslin list), with a D matrix which is either polynomial or constant, but not zero ss2des returns a descriptor system as list(‘des’,A,B,C,0,E) such that:

Sl=C*(s*E-A)^(-1)*B

If the flag “withD” is given, S=list(‘des’,A,B,C,D,E) with a D matrix of maximal rank.

Examples

s=`poly`_(0,'s');
G=[1/(s+1),s;1+s^2,3*s^3];Sl=`tf2ss`_(G);
S=ss2des(Sl)
S1=ss2des(Sl,"withD")
Des=`des2ss`_(S);Des(5)=`clean`_(Des(5))
Des1=`des2ss`_(S1)

See Also

• pol2des polynomial matrix to descriptor form
• tf2des transfer function to descriptor
• des2ss descriptor to state-space