% Chapter 3 : Example 3.19%             Reconstruction using sinc function%% Discrete-time Signal x1(n)Ts = 0.0002; Fs = 1/Ts; n = -25:1:25; nTs = n*Ts;x = exp(-1000*abs(nTs));% Analog Signal reconstructionDt = 0.00005;t = -0.005:Dt:0.005;xa = x * sinc(Fs*(ones(length(nTs),1)*t-nTs'*ones(1,length(t))));% checkerror = max(abs(xa - exp(-1000*abs(t))))% Plotssubplot(1,1,1)subplot(2,1,2);plot(t*1000,xa);xlabel('t in msec.'); ylabel('xa(t)')title('Reconstructed Signal from x1(n) using sinc function'); hold onstem(n*Ts*1000,x); hold off