//equation// s=%s; m=s^3+2*s^2+3*s+10; r=coeff(m) n=length(r); routh=[r([4,2]);r([3,1])]; routh=[routh;-det(routh)/routh(2,1),0]; t=routh(2:3,1:2); //extracting the square sub block of routh matrix routh=[routh;-det(t)/t(2,1),0] c=0; for i=1:n if (routh(i,1)<0) c=c+1; end end if(c>=1) printf("system is unstable") else ("system is stable") end