z3=0.5;
t1=2;
t2=3;

num=[z3];
den=[t1*t2, t1+t2, 1 0];
sys = tf(num,den);
bode(sys)
v=axis;
v(4) = -80;
axis(v);

set(1, 'PaperUnits', 'centimeters')
set(1, 'PaperPosition', [3 10 11 9])
print -deps 'obr4311.eps'

pause(1)
nyquist(sys)
v=axis;
v(4) = 0;
axis(v);

set(1, 'PaperUnits', 'centimeters')
set(1, 'PaperPosition', [3 10 11 9])
print -deps 'obr4310.eps'

