Bode Diagram50)0dB (edu-50itngaM-100-1500g)e-90d (eashP-180-27010-210-1100101102103Frequency (rad/s)Nyquist图： um=100;
den=[1 8 17 10];
w=logspace(-2,3,100); nyquist(num,den)
v=[-0.5,0.5,-0.5,0.5] axis(v ) grid
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Nyquist Diagram80 dB6422 dB-2 dBis4 dBAx6 dB y10 dB-10 dB-6 dB-4 dBarn0igaIm-2-4-6-8-20246810Real Axis局部放大图：
Nyquist Diagram12 dB0 dB-2 dB-4 dB0.84 dB-6 dB0.66 dB0.410 dB-10 dBis0.220 dB-20 dB Axyarn0igaIm-0.2-0.4-0.6-0.8-1-1-0.8-0.6-0.4-0.200.20.40.60.81Real Axis 7
Nyquist Diagram0.50 dB-2 dB-4 dB-6 dB0.4-10 dB0.30.2-20 dBis0.1 Axyarn0igaIm-0.1-0.2-0.3-0.4-0.5-0.5-0.4-0.3-0.2-0.100.10.20.30.40.5Real Axis阶跃响应曲线： num=100;
den=[1 8 17 10];
w=logspace(-2,3,100); G=tf(num,den);
G_c=feedback(G,1); t=0:1:100; step(G_c,t) grid
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Step Response1.81.61.41.2ed1uitlpAm0.80.60.40.200102030405060708090100Time (seconds)
（3）bode图 num=[4/3 4];
den=[conv([0.1,1],conv([0.02,1],[0.05,1])),0]; w=logspace(-2,3,100); bode(num,den,w) grid
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Bode Diagram100)50dB (edu0itngaM-50-100-45-90g)ed-135 (eash-180P-225-27010-210-1100101102103Frequency (rad/s)
Nyquist图
num=[4/3 4];
den=[conv([0.1,1],conv([0.02,1],[0.05,1])),0]; w=logspace(-2,3,100); nyquist(num,den)
v=[-0.5,0.5,-0.5,0.5] axis(v ) grid
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