暂且

Matlab/lab2.m

@@ -0,0 +1,54 @@
+figure(1);
+Ts = 1/50;
+t = 0:Ts:10-Ts;                     
+x = sawtooth(t,0.5);
+plot(t,x)
+xlabel('Time (seconds)')
+ylabel('Amplitude')
+
+figure(2);
+y = fft(x);   
+fs = 1/Ts;
+f = (0:length(y)-1)*fs/length(y);
+plot(f,abs(y))
+xlabel('Frequency (Hz)')
+ylabel('Magnitude')
+title('Magnitude')
+
+figure(3);
+Ts = 1/50;
+t = 0:Ts:10-Ts;                     
+x = exp(-3*t);
+plot(t,x)
+xlabel('Time (seconds)')
+ylabel('Amplitude')
+
+figure(4);
+y = fft(x);   
+fs = 1/Ts;
+f = (0:length(y)-1)*fs/length(y);
+plot(f,abs(y))
+xlabel('Frequency (Hz)')
+ylabel('Magnitude')
+title('Magnitude')
+
+
+figure(5);
+syms w t;
+X=w*sin(3/2*w)*2/3;
+subplot(2,2,1);
+ezplot(X,[-10,10]);
+iX=ifourier(F,t);
+subplot(2,2,2);
+ezplot(iX,[-10,10]);
+subplot(2,2,3);
+ezplot(abs(X),[-10,10]);
+im=imag(X);
+re=real(X);
+phase=atan(im/re);
+subplot(2,2,4);
+ezplot(phase,[-10,10]);
+
+figure(6);
+[H,W]=freqs([1,-1],[1,1]);
+plot(abs(W),H);