Man Scilab

ss2tf - conversion from state-space to transfer function

Calling Sequence

[h]=ss2tf(sl)

[Ds,NUM,chi]=ss2tf(sl)

[h]=ss2tf(sl,"b")

[Ds,NUM,chi]=ss2tf(sl,"b")

[h]=ss2tf(sl,rmax)

[Ds,NUM,chi]=ss2tf(sl,rmax)

Parameters

• sl : linear system ( syslin list)
• h : transfer matrix

Description

Called with three outputs [Ds,NUM,chi]=ss2tf(sl) returns the numerator polynomial matrix NUM , the characteristic polynomial chi and the polynomial part Ds separately i.e.:

h=NUM/chi + Ds
   
    

Method:

One uses the characteristic polynomial and det(A+Eij)=det(A)+C(i,j) where C is the adjugate matrix of A .

With rmax or "b" argument uses a block diagonalization of sl.A matrix and applies "Leverrier" algorithm on blocks. If given, rmax controls the conditionning (see bdiag).

Examples

s=poly(0,'s');
h=[1,1/s;1/(s^2+1),s/(s^2-2)]
sl=tf2ss(h);
h=clean(ss2tf(sl))
[Ds,NUM,chi]=ss2tf(sl)
 
  

See Also

tf2ss ,   syslin ,   nlev ,   glever ,  

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