1. 求极点
syms s
f1=(s^2+3)*(s+1)*(s+4)
f2=(s^3+3)(s+5)(s^2+4)
g1=expand(f1) g1 =s^4+5*s^3+7*s^2+15*s+12 //expand为展开多项式的意思
g2=expand(f2) g2 =s^6+4*s^4+5*s^5+23*s^3+12*s+15*s^2+60
a=[1,5,7,15,12],b=[1,5,4,23,15,12,60];
[z,p,k]=tf2zpk(a,b)
z =
0
0
-4.0000
0.0000 + 1.7321i
0.0000 - 1.7321i
-1.0000
p =
-5.0000
-1.4422
0.0000 + 2.0000i
0.0000 - 2.0000i
0.7211 + 1.2490i
0.7211 - 1.2490i
k =
1