3 Example 2.7b OGATA 4edition( Laplace transform, poles, zeros and gain)

Let us calculate the pole, the zeros and the gain by Scilab,the following transfer function:

\begin{displaymath}\frac{B(s)}{A(s)}=\frac{(4\cdot s^{2}+16\cdot s+12)}{s^{4}+12\cdot s^{3}+44\cdot s^{2}+48\cdot s} \end{displaymath}


Program in Scilab
s=%s
num=4*s^2+16*s+12;
den=(s)^4+12*s^3+44*s^2+48*s;
g=syslin('c',num/den);
[n d k]=factors(g)

Solution

 k  =
 
    4.  
 d  =
 
 
       d(1)
 
    s   
 
       d(2)
 
    2 + s   
 
       d(3)
 
    4 + s   
 
       d(4)
 
    6 + s   
 n  =
 
 
       n(1)
 
    1 + s   
 
       n(2)
 
    3 + s