From b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b Mon Sep 17 00:00:00 2001
From: priyanka
Date: Wed, 24 Jun 2015 15:03:17 +0530
Subject: initial commit / add all books

---
 40/CH8/EX8.5a/Exa_8_5a.sce | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)
 create mode 100755 40/CH8/EX8.5a/Exa_8_5a.sce

(limited to '40/CH8/EX8.5a')

diff --git a/40/CH8/EX8.5a/Exa_8_5a.sce b/40/CH8/EX8.5a/Exa_8_5a.sce
new file mode 100755
index 000000000..63e5aa5a4
--- /dev/null
+++ b/40/CH8/EX8.5a/Exa_8_5a.sce
@@ -0,0 +1,42 @@
+//properties of DFT
+//a1)product
+xn=[1 2 1 0];
+XDFT=dft(xn,-1)
+hn=xn.*xn
+HDFT=dft(hn,-1)
+HDFT1=1/4*(convol(XDFT,XDFT))
+HDFT1=[HDFT1,zeros(8:12)];
+HDFT2=[HDFT1(1:4);HDFT1(5:8);HDFT1(9:12)];
+HDFT3=[0 0 0 0];
+for i=1:4
+    for j=1:3
+        HDFT3(i)=HDFT3(i)+HDFT2(j,i);
+    end
+end
+disp(HDFT3,'DFT of x[n]^2 is');
+//a2)periodic convolution
+vn=convol(xn,xn);
+vn=[vn,zeros(8:12)];
+vn=[vn(1:4);vn(5:8);vn(9:12)];
+vn1=[0 0 0 0];
+for i=1:4
+    for j=1:3
+        vn1(i)=vn1(i)+vn(j,i);
+    end
+end
+VDFT=dft(vn1,-1);
+VDFT1=XDFT.*XDFT;
+disp(VDFT1,'DFT of x[n]*x[n] is');
+//a3)signal energy(parcewell's theorem)
+xn2=xn^2;
+E=0;
+for i=1:length(xn2)
+    E=E+abs(xn2(i));
+end
+XDFT2=XDFT^2
+E1=0;
+for i=1:length(XDFT2)
+    E1=E1+abs(XDFT2(i));
+end
+E,(1/4)*E1;
+disp(1/4*E1,'The energy of the signal is');
\ No newline at end of file
-- 
cgit