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n=0:10;
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t=linspace(-4,7); a=1; t0=2;
y=sinc(a*t-t0);
plot(t,y);
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t=linspace(-4,7); a=2;
t0=2;
y=sinc(a*t-t0); plot(t,y);
t=linspace(-4,7); a=1;
t0=2;
y=sinc(a*t-t0); plot(t,y);
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t=0:1/fs:1;
% ?¦Ì?¨º¡¤?¡Àe?a5Hz,10Hz,20Hz,30Hzf1=5; xa=cos(2*pi*f1*t); subplot(1,2,1); plot(t,xa);
axis([0,max(t),min(xa),max(xa)]); xlabel( 't(s)' );ylabel( 'Xa(t)' max(t)],[0,0]);
subplot(1,2,2);stem(t,xa, line([0,max(t)],[0,0]);
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axis([0,max(t),min(xa),max(xa)]); xlabel(
'n' );ylabel(
'X(n)'
);
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