Convert state-space representation to transfer function

   s=tf('s');
   G=(s^3+11*s^2+36*s+26)/(s^4+14.6*s^3+74.96*s^2+156.7*s+99.65);
   [A,B,C,D]=ssdata(G);
   [AA, BB, CC,DD] = balreal(A, B, C);
   [b,a] = ss2tf(AA,BB,CC,DD);

close all, clear all, clc
set(0, 'language', 'english')
colordef white; % Specify the plot background to be white

s = tf('s');

sys = (s^3+11*s^2+36*s+26) / (s^4+14.6*s^3+74.96*s^2+156.7*s+99.65)

[sysb, g] = balreal(sys);

tf(sysb)
g.'

sysr1 = tf( modred(sysb, [4], 'del') )
sysr2 = tf( modred(sysb, [3 4], 'del') )
sysr3 = tf( modred(sysb, [2 3 4], 'del') )

bode(sys,'r', sysr1,'g', sysr2,'b', sysr3,'k')
grid on
legend('sys', 'sysr1', 'sysr2', 'sysr3')

set(gcf, 'numbertitle', 'off')
set(gcf, 'MenuBar', 'none')

colordef black; % Specify the plot background to be black

Transfer function:
          s^3 + 11 s^2 + 36 s + 26
--------------------------------------------
s^4 + 14.6 s^3 + 74.96 s^2 + 156.7 s + 99.65
 
 
Transfer function:
          s^3 + 11 s^2 + 36 s + 26
--------------------------------------------
s^4 + 14.6 s^3 + 74.96 s^2 + 156.7 s + 99.65
 

ans =

    0.1374    0.0069    0.0003    0.0002

 
Transfer function:
 0.9961 s^2 + 1.196 s + 0.0398
--------------------------------
s^3 + 4.7 s^2 + 4.609 s + 0.1528
 
 
Transfer function:
  0.9961 s + 1.156
---------------------
s^2 + 4.661 s + 4.429
 
 
Transfer function:
  1.01
---------
s + 3.674