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-rw-r--r--2279/CH1/EX1.1/Ex1_1.sce10
-rw-r--r--2279/CH1/EX1.10/Ex1_10.sce16
-rw-r--r--2279/CH1/EX1.2/Ex1_2.sce10
-rw-r--r--2279/CH1/EX1.3/Ex1_3.sce17
-rw-r--r--2279/CH1/EX1.4/Ex1_4.sce29
-rw-r--r--2279/CH1/EX1.5/Ex1_5.sce14
-rw-r--r--2279/CH1/EX1.6/Ex1_6.sce22
-rw-r--r--2279/CH1/EX1.6/eg1_7.sce11
-rw-r--r--2279/CH1/EX1.7/Ex1_7.sce11
-rw-r--r--2279/CH1/EX1.8/Ex1_8.sce5
-rw-r--r--2279/CH2/EX2.1/Ex2_1.sce53
-rw-r--r--2279/CH2/EX2.2/Ex2_2.sce38
-rw-r--r--2279/CH2/EX2.3/Ex2_3.sce25
-rw-r--r--2279/CH3/EX3.10/Ex3_10.sce37
-rw-r--r--2279/CH3/EX3.11/Ex3_11.sce37
-rw-r--r--2279/CH3/EX3.13/Ex3_13.sce33
-rw-r--r--2279/CH3/EX3.14/Ex3_14.sce48
-rw-r--r--2279/CH3/EX3.15/Ex3_15.sce17
-rw-r--r--2279/CH3/EX3.16/Ex3_16.sce21
-rw-r--r--2279/CH3/EX3.17/Ex3_17.sce18
-rw-r--r--2279/CH3/EX3.18/Ex3_18.sce14
-rw-r--r--2279/CH4/EX4.1/Ex4_1.sce20
-rw-r--r--2279/CH4/EX4.10/Ex4_10.sce21
-rw-r--r--2279/CH4/EX4.11/Ex4_11.sce21
-rw-r--r--2279/CH4/EX4.13/Ex4_13.sce21
-rw-r--r--2279/CH4/EX4.14/Ex4_14.sce21
-rw-r--r--2279/CH4/EX4.15/Ex4_15.sce22
-rw-r--r--2279/CH4/EX4.16/Ex4_16.sce22
-rw-r--r--2279/CH4/EX4.17/Ex4_17.sce22
-rw-r--r--2279/CH4/EX4.18/Ex4_18.sce23
-rw-r--r--2279/CH4/EX4.19/Ex4_19.sce25
-rw-r--r--2279/CH4/EX4.2/Ex4_2.sce12
-rw-r--r--2279/CH4/EX4.20/Ex4_20.sce24
-rw-r--r--2279/CH4/EX4.21/Ex4_21.sce23
-rw-r--r--2279/CH4/EX4.23/Ex4_23.sce42
-rw-r--r--2279/CH4/EX4.24/Ex4_24.sce24
-rw-r--r--2279/CH4/EX4.26/Ex4_26.sce52
-rw-r--r--2279/CH4/EX4.27/Ex4_27.sce21
-rw-r--r--2279/CH4/EX4.30/Ex4_30.sce33
-rw-r--r--2279/CH4/EX4.5/Ex4_5.sce20
-rw-r--r--2279/CH4/EX4.6/Ex4_6.sce20
-rw-r--r--2279/CH5/EX5.1/Ex5_1.sce56
-rw-r--r--2279/CH5/EX5.14/Ex5_14.sce37
-rw-r--r--2279/CH5/EX5.15/Ex5_15.sce37
-rw-r--r--2279/CH5/EX5.16/Ex5_16.sce27
-rw-r--r--2279/CH5/EX5.17/Ex5_17.sce29
-rw-r--r--2279/CH5/EX5.18/Ex5_18.sce22
-rw-r--r--2279/CH5/EX5.19/Ex5_19.sce29
-rw-r--r--2279/CH5/EX5.2/Ex5_2.sce43
-rw-r--r--2279/CH5/EX5.20/Ex5_20.sce28
-rw-r--r--2279/CH5/EX5.21/Ex5_21.sce26
-rw-r--r--2279/CH5/EX5.22/Ex5_22.sce26
-rw-r--r--2279/CH5/EX5.24/Ex5_24.sce14
-rw-r--r--2279/CH5/EX5.25/Ex5_25.sce16
-rw-r--r--2279/CH5/EX5.3/Ex5_3.sce34
-rw-r--r--2279/CH5/EX5.32/Ex5_32.sce21
-rw-r--r--2279/CH5/EX5.37/Ex5_37.sce37
-rw-r--r--2279/CH5/EX5.4/Ex5_4.sce35
-rw-r--r--2279/CH5/EX5.5/Ex5_5.sce41
-rw-r--r--2279/CH5/EX5.6/Ex5_6.sce21
-rw-r--r--2279/CH5/EX5.7/Ex5_7.sce50
-rw-r--r--2279/CH5/EX5.8/Ex5_8.sce23
-rw-r--r--2279/CH6/EX6.1/Ex6_1.sce27
-rw-r--r--2279/CH6/EX6.2/Ex6_2.sce19
-rw-r--r--2279/CH6/EX6.3/Ex6_3.sce24
-rw-r--r--2279/CH6/EX6.4/Ex6_4.sce41
-rw-r--r--2279/CH6/EX6.6/Ex6_6.sce16
-rw-r--r--2279/CH6/EX6.7/Ex6_7.sce53
-rw-r--r--2279/CH7/EX7.1/eg_7_1.sce23
-rw-r--r--2279/CH7/EX7.10/Ex7_10.sce22
-rw-r--r--2279/CH7/EX7.16/Ex7_16.sce32
-rw-r--r--2279/CH7/EX7.17/Ex7_17.sce32
-rw-r--r--2279/CH7/EX7.18/Ex7_18.sce27
-rw-r--r--2279/CH7/EX7.19/Ex7_19.sce25
-rw-r--r--2279/CH7/EX7.24/Ex7_24.sce22
-rw-r--r--2279/CH7/EX7.26/Ex7_26.sce36
-rw-r--r--2279/CH7/EX7.3/Ex7_3.sce32
-rw-r--r--2279/CH7/EX7.4/Ex7_4.sce30
-rw-r--r--2279/CH7/EX7.5/Ex7_5.sce23
-rw-r--r--2279/CH7/EX7.6/Ex7_6.sce23
-rw-r--r--2279/CH7/EX7.7/Ex7_7.sce23
-rw-r--r--2279/CH7/EX7.8/Ex7_8.sce31
-rw-r--r--2279/CH7/EX7.9/Ex7_9.sce31
83 files changed, 2219 insertions, 0 deletions
diff --git a/2279/CH1/EX1.1/Ex1_1.sce b/2279/CH1/EX1.1/Ex1_1.sce
new file mode 100644
index 000000000..1157511fd
--- /dev/null
+++ b/2279/CH1/EX1.1/Ex1_1.sce
@@ -0,0 +1,10 @@
+clf
+clc
+clear
+t=[-20:0.01:20];
+for i=1:length(t)
+ x(i)=2;
+end
+plot(t,x);
+xtitle("x(t)=2 for all t","time","amplitude");
+xgrid(5)
diff --git a/2279/CH1/EX1.10/Ex1_10.sce b/2279/CH1/EX1.10/Ex1_10.sce
new file mode 100644
index 000000000..e9a16362a
--- /dev/null
+++ b/2279/CH1/EX1.10/Ex1_10.sce
@@ -0,0 +1,16 @@
+clear
+clf
+clc
+n=-20:1:20;
+for i=1:length(n)
+ x(i)=0.5;
+end
+subplot(2,1,1)
+plot(n,x,".");
+xtitle("x(n)=0.5 for all n","number of samples","amplitude");
+xgrid(5)
+y=0.5*x;
+subplot(2,1,2)
+plot(n,y,".");
+xtitle("y(n)=0.5*x(n) for all n","number of samples","amplitude");
+xgrid(5)
diff --git a/2279/CH1/EX1.2/Ex1_2.sce b/2279/CH1/EX1.2/Ex1_2.sce
new file mode 100644
index 000000000..4757f4c1d
--- /dev/null
+++ b/2279/CH1/EX1.2/Ex1_2.sce
@@ -0,0 +1,10 @@
+clf
+clear
+clc
+t=[-20:0.01:20];
+for i=1:length(t)
+ x=2*t;
+end
+plot(t,x);
+xtitle("x(t)=2*t for all t","time","amplitude");
+xgrid(5)
diff --git a/2279/CH1/EX1.3/Ex1_3.sce b/2279/CH1/EX1.3/Ex1_3.sce
new file mode 100644
index 000000000..90cc3f294
--- /dev/null
+++ b/2279/CH1/EX1.3/Ex1_3.sce
@@ -0,0 +1,17 @@
+clc
+clear
+clf
+interval=input('enter the value of time interval T between two samples');
+t=(-20*interval):interval:(20*interval);
+for i=1:length(t)
+ if t(i)<0 then
+ x(i)=-1;
+ elseif t(i)>0 then
+ x(i)=1;
+ else
+ x(i)=0;
+ end
+end
+plot(t,x,".");
+xtitle("x(t)=1 for positive values of t..., x(t)=0 for t=0...., x(t)=-1 for negative values of t","time","amplitude");
+xgrid(5)
diff --git a/2279/CH1/EX1.4/Ex1_4.sce b/2279/CH1/EX1.4/Ex1_4.sce
new file mode 100644
index 000000000..1f689f557
--- /dev/null
+++ b/2279/CH1/EX1.4/Ex1_4.sce
@@ -0,0 +1,29 @@
+clear
+clf
+clc
+t=-20:0.01:20;
+for i=1:length(t)
+ if t(i)>0 then
+ x1(i)=0.5;
+ else
+ x1(i)=-0.5;
+ end
+end
+subplot(3,1,1)
+plot(t,x1);
+xtitle("x1(t)=-0.5 for t<0 and x1(t)=0.5 for t>0","time","amplitude");
+xgrid(5);
+subplot(3,1,2)
+for i=1:length(t)
+ x2(i)=-t(i);
+end
+plot(t,x2);
+xtitle("x2(t)=-t for all t","time","amplitude");
+xgrid(5);
+subplot(3,1,3)
+for i=1:length(t)
+ x3(i)=t(i).^2;
+end
+plot(t,x3);
+xtitle("x3(t)=t^2 for all t","time","amplitude");
+xgrid(5);
diff --git a/2279/CH1/EX1.5/Ex1_5.sce b/2279/CH1/EX1.5/Ex1_5.sce
new file mode 100644
index 000000000..4f3bb9b34
--- /dev/null
+++ b/2279/CH1/EX1.5/Ex1_5.sce
@@ -0,0 +1,14 @@
+clear
+clf
+clc
+n=-20:1:20;
+for i=1:length(n)
+ if n(i)>=0 then
+ x(i)=2;
+ else
+ x(i)=0;
+ end
+end
+plot(n,x,".");
+xtitle("x(n)=0 for n<0 and x(n)=2 for n>=0","number of samples","amplitude");
+xgrid(5)
diff --git a/2279/CH1/EX1.6/Ex1_6.sce b/2279/CH1/EX1.6/Ex1_6.sce
new file mode 100644
index 000000000..0af1f46bd
--- /dev/null
+++ b/2279/CH1/EX1.6/Ex1_6.sce
@@ -0,0 +1,22 @@
+clc
+clear
+clf
+n1=-2:1:2;
+x1=-2:1:2;
+subplot(3,1,1)
+plot(n1,x1,".");
+xtitle("x1(n)","n","x1(n)");
+xgrid(5)
+n=-5:1:5;
+for i=1:length(n)
+ x2(i)=n(i);
+ x3(i)=2-n(i);
+end
+subplot(3,1,2);
+plot(n,x2,".");
+xtitle("x2(n)","n","x2(n)");
+xgrid(5);
+subplot(3,1,3);
+plot(n,x3,".");
+xtitle("x3(n)","n","x3(n)");
+xgrid(5);
diff --git a/2279/CH1/EX1.6/eg1_7.sce b/2279/CH1/EX1.6/eg1_7.sce
new file mode 100644
index 000000000..d090d46d7
--- /dev/null
+++ b/2279/CH1/EX1.6/eg1_7.sce
@@ -0,0 +1,11 @@
+clear
+clf
+clc
+interval=input('enter the sampling interval');
+n=[-20:1:20];
+t=n*interval
+for i=1:length(t)
+ x(i)=2*t(i);
+end
+plot(t,x,".");
+xtitle("sampled function of x(t)=2*t for all t","number of samples","amplitude");
diff --git a/2279/CH1/EX1.7/Ex1_7.sce b/2279/CH1/EX1.7/Ex1_7.sce
new file mode 100644
index 000000000..d090d46d7
--- /dev/null
+++ b/2279/CH1/EX1.7/Ex1_7.sce
@@ -0,0 +1,11 @@
+clear
+clf
+clc
+interval=input('enter the sampling interval');
+n=[-20:1:20];
+t=n*interval
+for i=1:length(t)
+ x(i)=2*t(i);
+end
+plot(t,x,".");
+xtitle("sampled function of x(t)=2*t for all t","number of samples","amplitude");
diff --git a/2279/CH1/EX1.8/Ex1_8.sce b/2279/CH1/EX1.8/Ex1_8.sce
new file mode 100644
index 000000000..09c51e6d7
--- /dev/null
+++ b/2279/CH1/EX1.8/Ex1_8.sce
@@ -0,0 +1,5 @@
+x=poly([-4 2 1],'t','c')
+a=horner(x,0)
+b=horner(x,-2)
+disp(a)
+disp(b)
diff --git a/2279/CH2/EX2.1/Ex2_1.sce b/2279/CH2/EX2.1/Ex2_1.sce
new file mode 100644
index 000000000..af9ce6d2f
--- /dev/null
+++ b/2279/CH2/EX2.1/Ex2_1.sce
@@ -0,0 +1,53 @@
+//Example 2.1
+clf
+clear
+clc
+t=[-10:0.01:10];
+for i=1:length(t)
+ if t(i)>= -0.5 & t(i)<= 0.5 then
+ x(i)=t(i)+0.5;
+ elseif t(i)>0.5 & t(i)<=1.5 then
+ x(i)=1.5-t(i);
+ else
+ x(i)=0;
+ end
+end
+subplot(3,1,1);
+plot2d(t,x,rect=[-4 0 4 2]);
+xtitle("x(t) vs t","t in sec","x(t)");
+subplot(3,1,2);
+plot2d(t-1,x,rect=[-4 0 4 2]);
+xtitle("x(t+1) vs t","t in sec","x(t+1)");
+subplot(3,1,3);
+plot2d(t+2,x,rect=[-4 0 4 2]);
+xtitle("x(t-2) vs t","t in sec","x(t-2)");
+xset('window',1);
+subplot(3,1,1);
+plot2d(-t,x,rect=[-4 0 4 2]);
+xtitle("x(-t) vs t","t in sec","x(-t)");
+subplot(3,1,2);
+plot2d(t/2,x,rect=[-4 0 4 2]);
+xtitle("x(2t) vs t","t in sec","x(2t)");
+subplot(3,1,3);
+plot2d(t*2,x,rect=[-4 0 4 2]);
+xtitle("x(t/2) vs t","t in sec","x(t/2)");
+xset('window',2);
+subplot(3,1,1);
+plot2d(-t-1,x,rect=[-4 0 4 2]);
+xtitle("x(-t+1) vs t","t in sec","x(-t+1)");
+subplot(3,1,2);
+plot2d(-t+2,x,rect=[-4 0 4 2]);
+xtitle("x(-t-2) vs t","t in sec","x(-t-2)");
+subplot(3,1,3);
+plot2d(-t/2,x,rect=[-4 0 4 2]);
+xtitle("x(-2t) vs t","t in sec","x(-2t)");
+xset('window',3);
+subplot(3,1,1);
+plot2d(-t*2,x,rect=[-4 0 4 2]);
+xtitle("x(-t/2) vs t","t in sec","x(-t/2)");
+subplot(3,1,2);
+plot2d(-(t-1)/2,x,rect=[-4 0 4 2]);
+xtitle("x(-2t+1) vs t","t in sec","x(-2t+1)");
+subplot(3,1,3);
+plot2d(-(t+2)/2,x,rect=[-4 0 4 2]);
+xtitle("x(-2t-2) vs t","t in sec","x(-2t-2)");
diff --git a/2279/CH2/EX2.2/Ex2_2.sce b/2279/CH2/EX2.2/Ex2_2.sce
new file mode 100644
index 000000000..13508629a
--- /dev/null
+++ b/2279/CH2/EX2.2/Ex2_2.sce
@@ -0,0 +1,38 @@
+//Example 2.2
+clf
+clear
+clc
+t=[-10:0.01:10];
+for i=1:length(t)
+ if t(i)>= -2 & t(i)<=4 then
+ x(i)=(t(i)+2)/6;
+ else
+ x(i)=0;
+ end
+end
+subplot(3,1,1);
+plot2d(t,x,rect=[-10 0 10 2]);
+xtitle("x(t) vs t","t in sec","x(t)");
+subplot(3,1,2);
+plot2d(t-1,x,rect=[-10 0 10 2]);
+xtitle("x(t+1) vs t","t in sec","x(t+1)");
+subplot(3,1,3);
+plot2d(t+1,x,rect=[-10 0 10 2]);
+xtitle("x(t-1) vs t","t in sec","x(t-1)");
+xset('window',1);
+subplot(3,1,1);
+plot2d(t/2,x,rect=[-10 0 10 2]);
+xtitle("x(2t) vs t","t in sec","x(2t)");
+subplot(3,1,2);
+plot2d(2*t,x,rect=[-10 0 10 2]);
+xtitle("x(t/2) vs t","t in sec","x(t/2)");
+subplot(3,1,3);
+plot2d(-t/3,x,rect=[-10 0 10 2]);
+xtitle("x(-3t) vs t","t in sec","x(-3t)");
+xset('window',2);
+subplot(3,1,1);
+plot2d(-(t-3),x,rect=[-10 0 10 2]);
+xtitle("x(3-t) vs t","t in sec","x(3-t)");
+subplot(3,1,2);
+plot2d(-(t-2)/2,x,rect=[-10 0 10 2]);
+xtitle("x(-2t+2) vs t","t in sec","x(-2t+2)");
diff --git a/2279/CH2/EX2.3/Ex2_3.sce b/2279/CH2/EX2.3/Ex2_3.sce
new file mode 100644
index 000000000..2168406b9
--- /dev/null
+++ b/2279/CH2/EX2.3/Ex2_3.sce
@@ -0,0 +1,25 @@
+//Example 2.3
+clear
+clc
+clf
+n=-20:1:20;
+x=[zeros(1,19),1,1,2,3,4,0.5, zeros(1,16)];
+subplot(3,1,1);
+plot(n,x,".");
+xtitle("x(n) vs n","n","x(n)");
+subplot(3,1,2);
+plot(n+3,x,'.');
+xtitle("x(n-3) vs n","n","x(n-3)");
+subplot(3,1,3);
+plot(n-2,x,'.');
+xtitle("x(n+2) vs n","n","x(n+2)");
+figure(1)
+subplot(3,1,1);
+plot(-n,x,'.');
+xtitle("x(-n) vs n","n","x(-n)");
+subplot(3,1,2);
+plot(-n+2,x,'.');
+xtitle("x(-n+2) vs n","n","x(-n+2)");
+subplot(3,1,3)
+plot(-n-3,x,'.')
+xtitle("x(-n-3) vs n","n","x(-n-3)");
diff --git a/2279/CH3/EX3.10/Ex3_10.sce b/2279/CH3/EX3.10/Ex3_10.sce
new file mode 100644
index 000000000..08efe6700
--- /dev/null
+++ b/2279/CH3/EX3.10/Ex3_10.sce
@@ -0,0 +1,37 @@
+//Example 3.10
+clc
+clear all
+t=0:0.01:20;
+function y=signal(x)
+ y=x
+endfunction
+//Assume v(t) as ramp signal
+v1=t;
+v2=t+2;
+//Assume R=1
+i1=signal(v1)
+i2=signal(v2)
+a=2;
+b=2;
+subplot(4,2,1)
+plot(t,a*v1)
+xtitle("a*v1(t)","t in sec","a*v1(t)");
+subplot(4,2,2)
+plot(t,signal(a*v1))
+xtitle("a*i1(t)","t in sec","a*i1(t)");
+subplot(4,2,3)
+plot(t,b*v2)
+xtitle("b*v2(t)","t in sec","b*v2(t)");
+subplot(4,2,4)
+plot(t,signal(b*v2))
+xtitle("b*i2(t)","t in sec","b*i2(t)");
+c=(a*v1)+(b*v2);
+subplot(4,2,5)
+plot(t,c)
+xtitle("v3(t)","t in sec","v3(t)");
+subplot(4,2,6)
+plot(t,signal(c))
+xtitle("i3(t)","t in sec","i3(t)");
+subplot(4,2,8)
+plot(t,signal(a*v1)+signal(b*v2))
+xtitle("LINEAR SYSTEM","t in sec","a*i1(t)+b*i2(t)");
diff --git a/2279/CH3/EX3.11/Ex3_11.sce b/2279/CH3/EX3.11/Ex3_11.sce
new file mode 100644
index 000000000..c60dfd651
--- /dev/null
+++ b/2279/CH3/EX3.11/Ex3_11.sce
@@ -0,0 +1,37 @@
+//Example 3.11
+clc
+clear all
+t=0:0.001:0.5;
+function i=signal(v)
+ i=exp(v);
+endfunction
+//Assume v(t) as ramp signal
+x1=2*ones(1,length(t));
+x2=t+2;
+//Assume R=1
+y1=signal(x1)
+y2=signal(x2)
+a=2;
+b=2;
+subplot(4,2,1)
+plot(t,a*x1)
+xtitle("a*x1(t)","t in sec","a*x1(t)");
+subplot(4,2,2)
+plot(t,signal(a*x1))
+xtitle("a*y1(t)","t in sec","a*y1(t)");
+subplot(4,2,3)
+plot(t,b*x2)
+xtitle("b*x2(t)","t in sec","b*x2(t)");
+subplot(4,2,4)
+plot(t,signal(b*x2))
+xtitle("b*y2(t)","t in sec","b*y2(t)");
+c=(a*x1)+(b*x2);
+subplot(4,2,5)
+plot(t,c)
+xtitle("x3(t)","t in sec","x3(t)");
+subplot(4,2,6)
+plot(t,signal(c))
+xtitle("y3(t)","t in sec","y3(t)");
+subplot(4,2,8)
+plot(t,signal(a*x1)+signal(b*x2))
+xtitle("NON-LINEAR SYSTEM","t in sec","a*y1(t)+b*y2(t)");
diff --git a/2279/CH3/EX3.13/Ex3_13.sce b/2279/CH3/EX3.13/Ex3_13.sce
new file mode 100644
index 000000000..86f976a05
--- /dev/null
+++ b/2279/CH3/EX3.13/Ex3_13.sce
@@ -0,0 +1,33 @@
+//Example 3.13
+clear;
+clc;
+x1 = [1,1,1,1];
+x2 = [2,2,2,2];
+a = 1;
+b = 1;
+for n = 1:length(x1)
+ x3(n) = a*x1(n)+b*x2(n);
+end
+for n = 1:length(x1)
+ y1(n) = x1(n)^2;
+ y2(n) = x2(n)^2;
+ y3(n) = x3(n)^2;
+end
+for n = 1:length(y1)
+ z(n) = a*y1(n)+b*y2(n);
+end
+count = 0;
+for n =1:length(y1)
+ if(y3(n)== z(n))
+ count = count+1;
+ end
+end
+if(count == length(y3))
+ disp('Since It satisifies the superposition principle')
+ disp('The given system is a Linear system')
+ y3
+ z
+ else
+ disp('Since It does not satisify the superposition principle')
+ disp('The given system is a Non-Linear system')
+end
diff --git a/2279/CH3/EX3.14/Ex3_14.sce b/2279/CH3/EX3.14/Ex3_14.sce
new file mode 100644
index 000000000..94cefa850
--- /dev/null
+++ b/2279/CH3/EX3.14/Ex3_14.sce
@@ -0,0 +1,48 @@
+//Example 3.14
+clear;
+clc;
+to = 2; //Assume the amount of time shift =2
+T=10;
+t=0:0.1:T;
+for i=1:length(t)
+ if (t(i)>=0 & t(i)<1)
+ x1(i) = t(i);
+ x2(i)=0;
+ elseif (t(i)>=1 & t(i)<2) then
+ x1(i)=1;
+ x2(i)=t(i)-1;
+ elseif (t(i)>=2 & t(i)<3) then
+ x1(i)=2;
+ x2(i)=1;
+ elseif (t(i)>=3 & t(i)<4)
+ x1(i)=0;
+ x2(i)=2;
+ else
+ x1(i)=0;
+ x2(i)=0;
+ end
+y1(i) = 2*(x1(i));
+y2(i)=2*x2(i);
+end
+figure(0);
+subplot(2,1,1);
+plot(t,x1);
+xtitle("x1(t)","t","x1(t)");
+subplot(2,1,2);
+plot(t,y1);
+xtitle("y1(t)=2*x1(t)","t","y1(t)");
+figure(1);
+subplot(2,1,1);
+plot(t,x2);
+xtitle("x2(t)","t","x2(t)");
+subplot(2,1,2);
+plot(t,y2);
+xtitle("y2(t)=2*x2(t)=2*x1(t-1)=y1(t-1)","t","y2(t)");
+//First shift the input signal only
+Input_shift = 2*(x1(T-to));
+Output_shift = y1(T-to);
+if(Input_shift == Output_shift)
+ disp('The given system is a Time In-variant system');
+else
+ disp('The given system is a Time Variant system');
+end
diff --git a/2279/CH3/EX3.15/Ex3_15.sce b/2279/CH3/EX3.15/Ex3_15.sce
new file mode 100644
index 000000000..564986888
--- /dev/null
+++ b/2279/CH3/EX3.15/Ex3_15.sce
@@ -0,0 +1,17 @@
+//Example 3.15
+clear;
+clc;
+to = 2; //Assume the amount of time shift =2
+T=10;
+for t = 1:0.01:T
+ x(t) = sin(t);
+ y(t) = sin(2*t);
+end
+//First shift the input signal only
+Input_shift = x(T-to);
+Output_shift = y(T-to);
+if(Input_shift == Output_shift)
+ disp('The given system is a Time In-variant system');
+else
+ disp('The given system is a Time Variant system');
+end
diff --git a/2279/CH3/EX3.16/Ex3_16.sce b/2279/CH3/EX3.16/Ex3_16.sce
new file mode 100644
index 000000000..a1ce9199a
--- /dev/null
+++ b/2279/CH3/EX3.16/Ex3_16.sce
@@ -0,0 +1,21 @@
+//Example 3.16
+clear;
+clc;
+no = 2; //Assume the amount of time shift =2
+L = 10; //Length of given signal
+for n = 1:L
+ x(n)=sin(n);
+ end
+ n=2;
+ for i=1:L
+ y(i)=x(n-1);
+ n=n+1;
+ end
+//First shift the input signal only
+Input_shift = x(L-no);
+Output_shift = y(L-no);
+if(Input_shift == Output_shift)
+ disp('The given discrete system is a Time In-variant system');
+else
+ disp('The given discrete system is a Time Variant system');
+end
diff --git a/2279/CH3/EX3.17/Ex3_17.sce b/2279/CH3/EX3.17/Ex3_17.sce
new file mode 100644
index 000000000..ab7272f88
--- /dev/null
+++ b/2279/CH3/EX3.17/Ex3_17.sce
@@ -0,0 +1,18 @@
+//Example 3.17
+clear;
+clc;
+no = 2; //Assume the amount of time shift =2
+L = 10; //Length of given signal
+for n = 1:L
+ x(n)=sin(n);
+ y(n)=-sin(n);
+ end
+
+//First shift the input signal only
+Input_shift = x(L-no);
+Output_shift = y(L-no);
+if(Input_shift == Output_shift)
+ disp('The given discrete system is a Time In-variant system');
+else
+ disp('The given discrete system is a Time Variant system');
+end
diff --git a/2279/CH3/EX3.18/Ex3_18.sce b/2279/CH3/EX3.18/Ex3_18.sce
new file mode 100644
index 000000000..ea9b05583
--- /dev/null
+++ b/2279/CH3/EX3.18/Ex3_18.sce
@@ -0,0 +1,14 @@
+//Example 3.18
+clc
+clear
+t=0:0.01:10;
+for i=1:length(t)
+ x(i)=sin(i);
+ y(i)=2*x(i);
+ z(i)=0.5*y(i);
+end
+if (x==z) then
+ disp("The given system is invertible");
+else
+ disp("the Given system is non-invertible");
+end
diff --git a/2279/CH4/EX4.1/Ex4_1.sce b/2279/CH4/EX4.1/Ex4_1.sce
new file mode 100644
index 000000000..16df5cecc
--- /dev/null
+++ b/2279/CH4/EX4.1/Ex4_1.sce
@@ -0,0 +1,20 @@
+//Example 4.1
+//Convolution sum of x[n] and h[n]
+clc
+clear
+n=[0 1 2];
+n1=0:4;
+x=[0.5 0.5 0.5];
+h=[3 2 1];
+y=convol(h,x)
+disp("Convolution of x[n] and h[n] is...")
+disp(y)
+subplot(3,1,1)
+xtitle("","....................n","x[n]");
+plot2d3('gnn',n,x,5);
+subplot(3,1,2)
+xtitle("","....................n","h[n]");
+plot2d3('gnn',n,h,5);
+subplot(3,1,3)
+xtitle("",".............................n","y[n]");
+plot2d3('gnn',n1,y,5);
diff --git a/2279/CH4/EX4.10/Ex4_10.sce b/2279/CH4/EX4.10/Ex4_10.sce
new file mode 100644
index 000000000..09fe34655
--- /dev/null
+++ b/2279/CH4/EX4.10/Ex4_10.sce
@@ -0,0 +1,21 @@
+//Example 4.10
+//Convolution sum of x[n] and h[n]
+clc
+clear
+n=0:2;
+n1=0:4;
+x=[0.5 0.5 0.5];
+h=[3 2 1];
+A=[x 0 0;0 x 0; 0 0 x];
+y=A'*h'
+disp("Convolution of x[n] and h[n] is...")
+disp(y)
+subplot(3,1,1)
+xtitle("input signal x(n)","....................n","x[n]");
+plot(n,x,'.');
+subplot(3,1,2)
+xtitle("system response h(n)","....................n","h[n]");
+plot(n,h,'.');
+subplot(3,1,3)
+xtitle("output signal y(n)",".............................n","y[n]");
+plot(n1,y,'.');
diff --git a/2279/CH4/EX4.11/Ex4_11.sce b/2279/CH4/EX4.11/Ex4_11.sce
new file mode 100644
index 000000000..9563bb9b3
--- /dev/null
+++ b/2279/CH4/EX4.11/Ex4_11.sce
@@ -0,0 +1,21 @@
+//Example 4.11
+//Convolution sum of x[n] and h[n]
+clc
+clear
+n=-1:1;
+n1=-2:2;
+x=[0.5 0.5 0.5];
+h=[3 2 1];
+A=[x 0 0;0 x 0; 0 0 x];
+y=A'*h'
+disp("Convolution of x[n] and h[n] is...")
+disp(y)
+subplot(3,1,1)
+xtitle("input signal x(n)","....................n","x[n]");
+plot2d3('gnn',n,x,5);
+subplot(3,1,2)
+xtitle("system response h(n)","....................n","h[n]");
+plot2d3('gnn',n,h,5);
+subplot(3,1,3)
+xtitle("output signal y(n)",".............................n","y[n]");
+plot2d3('gnn',n1,y,5);
diff --git a/2279/CH4/EX4.13/Ex4_13.sce b/2279/CH4/EX4.13/Ex4_13.sce
new file mode 100644
index 000000000..58b5521a4
--- /dev/null
+++ b/2279/CH4/EX4.13/Ex4_13.sce
@@ -0,0 +1,21 @@
+//Example 4.13
+//Convolution sum of x[n] and h[n]
+clc
+clear
+n=0:100;
+n1=0:200;
+for i=1:length(n)
+ x(i)=n(i);
+ h(i)=1;
+end
+y=convol(x,h);
+disp(y)
+subplot(3,1,1)
+xtitle("input signal x(n)","....................n","x[n]");
+plot(n,x,'.');
+subplot(3,1,2)
+xtitle("system response h(n)","....................n","h[n]");
+plot(n,h,'.');
+subplot(3,1,3)
+xtitle("output signal y(n)",".............................n","y[n]");
+plot(n1,y,'.');
diff --git a/2279/CH4/EX4.14/Ex4_14.sce b/2279/CH4/EX4.14/Ex4_14.sce
new file mode 100644
index 000000000..06942d2f9
--- /dev/null
+++ b/2279/CH4/EX4.14/Ex4_14.sce
@@ -0,0 +1,21 @@
+//Example 4.14
+//Convolution sum of x[n] and h[n]
+clc
+clear
+n=0:100;
+n1=0:200;
+a=0.7//assume the constant a=0.7
+for i=1:length(n)
+ x(i)=a^n(i);
+ h(i)=1;
+end
+y=convol(x,h);
+subplot(3,1,1)
+xtitle("input signal x(n)","....................n","x[n]");
+plot(n,x,'.');
+subplot(3,1,2)
+xtitle("system response h(n)","....................n","h[n]");
+plot(n,h,'.');
+subplot(3,1,3)
+xtitle("output signal y(n)",".............................n","y[n]");
+plot(n1,y,'.');
diff --git a/2279/CH4/EX4.15/Ex4_15.sce b/2279/CH4/EX4.15/Ex4_15.sce
new file mode 100644
index 000000000..19973d1c5
--- /dev/null
+++ b/2279/CH4/EX4.15/Ex4_15.sce
@@ -0,0 +1,22 @@
+//Example 4.15
+//Convolution sum of x[n] and h[n]
+clc
+clear
+n1=-100:1:0;
+n2=0:100;
+n3=-100:100;
+a=0.5//assume the constant a=0.5
+for i=1:length(n1)
+ x(i)=a^-n1(i);
+ h(i)=a^n1(i);
+end
+y=convol(x,h);
+subplot(3,1,1)
+xtitle("input signal x(n)","....................n","x[n]");
+plot(n1,x,'.');
+subplot(3,1,2)
+xtitle("system response h(n)","....................n","h[n]");
+plot(n2,h,'.');
+subplot(3,1,3)
+xtitle("output signal y(n)",".............................n","y[n]");
+plot(n3,y,'.');
diff --git a/2279/CH4/EX4.16/Ex4_16.sce b/2279/CH4/EX4.16/Ex4_16.sce
new file mode 100644
index 000000000..516f52d8f
--- /dev/null
+++ b/2279/CH4/EX4.16/Ex4_16.sce
@@ -0,0 +1,22 @@
+//Example 4.16
+//Convolution sum of x[n] and h[n]
+clc
+clear
+n1=-100:-2;
+n2=2:100;
+n3=-98:98;
+a=1/2//assume the constant a=1/2
+for i=1:length(n1)
+ x(i)=a^-n1(i);
+ h(i)=1;
+end
+y=convol(x,h);
+subplot(3,1,1)
+xtitle("input signal x(n)","....................n","x[n]");
+plot(n1,x,'.');
+subplot(3,1,2)
+xtitle("system response h(n)","....................n","h[n]");
+plot(n2,h,'.');
+subplot(3,1,3)
+xtitle("output signal y(n)",".............................n","y[n]");
+plot(n3,y,'.');
diff --git a/2279/CH4/EX4.17/Ex4_17.sce b/2279/CH4/EX4.17/Ex4_17.sce
new file mode 100644
index 000000000..f72c2aa29
--- /dev/null
+++ b/2279/CH4/EX4.17/Ex4_17.sce
@@ -0,0 +1,22 @@
+//Example 4.17
+//Convolution sum of x[n] and h[n]
+clc
+clear
+n1=2:12;
+n2=4:14;
+n3=6:26;
+a=1/3//assume the constant a=1/3
+for i=1:length(n1)
+ x(i)=a^-n1(i);
+ h(i)=1;
+end
+y=convol(x,h);
+subplot(3,1,1)
+xtitle("input signal x(n)","....................n","x[n]");
+plot(n1,x,'.');
+subplot(3,1,2)
+xtitle("system response h(n)","....................n","h[n]");
+plot(n2,h,'.');
+subplot(3,1,3)
+xtitle("output signal y(n)",".............................n","y[n]");
+plot(n3,y,'.');
diff --git a/2279/CH4/EX4.18/Ex4_18.sce b/2279/CH4/EX4.18/Ex4_18.sce
new file mode 100644
index 000000000..b8e2032bc
--- /dev/null
+++ b/2279/CH4/EX4.18/Ex4_18.sce
@@ -0,0 +1,23 @@
+//Example 4.18
+//Convolution sum of x[n] and h[n]
+clc
+clear
+n1=-100:0;
+n2=0:100;
+n3=-100:100;
+b=0.8//assume the constant b=0.4
+a=0.8//assume the constant a=0.8
+for i=1:length(n1)
+ x(i)=a^n1(i);
+ h(i)=b^n1(i);
+end
+y=convol(x,h);
+subplot(3,1,1)
+xtitle("input signal x(n)","....................n","x[n]");
+plot(n1,x,'.');
+subplot(3,1,2)
+xtitle("system response h(n)","....................n","h[n]");
+plot(n2,h,'.');
+subplot(3,1,3)
+xtitle("output signal y(n)",".............................n","y[n]");
+plot(n3,y,'.');
diff --git a/2279/CH4/EX4.19/Ex4_19.sce b/2279/CH4/EX4.19/Ex4_19.sce
new file mode 100644
index 000000000..97630f089
--- /dev/null
+++ b/2279/CH4/EX4.19/Ex4_19.sce
@@ -0,0 +1,25 @@
+//Example 4.19
+//Convolution sum of x[n] and h[n]
+clc
+clear
+n1=0:9;
+n2=0:100;
+n3=0:109;
+b=0.8//assume the constant b=0.4
+a=0.8//assume the constant a=0.8
+for i=1:length(n1)
+ x(i)=a^n1(i);
+end
+for j=1:length(n2)
+ h(j)=b^n2(j);
+end
+y=convol(x,h);
+subplot(3,1,1)
+xtitle("input signal x(n)","....................n","x[n]");
+plot(n1,x,'.');
+subplot(3,1,2)
+xtitle("system response h(n)","....................n","h[n]");
+plot(n2,h,'.');
+subplot(3,1,3)
+xtitle("output signal y(n)",".............................n","y[n]");
+plot(n3,y,'.');
diff --git a/2279/CH4/EX4.2/Ex4_2.sce b/2279/CH4/EX4.2/Ex4_2.sce
new file mode 100644
index 000000000..573c7465b
--- /dev/null
+++ b/2279/CH4/EX4.2/Ex4_2.sce
@@ -0,0 +1,12 @@
+//Example 4.2
+//Convolution sum of x[n] and h[n]
+clc
+clear
+n=-1:1;
+n1=-2:2;
+x=[0.5 0.5 0.5];
+h=[3 2 1];
+y=coeff(poly(h,'z','c')*poly(x,'z','c'))
+disp("Convolution of x[n] and h[n] is...")
+disp(y)
+
diff --git a/2279/CH4/EX4.20/Ex4_20.sce b/2279/CH4/EX4.20/Ex4_20.sce
new file mode 100644
index 000000000..a2845b430
--- /dev/null
+++ b/2279/CH4/EX4.20/Ex4_20.sce
@@ -0,0 +1,24 @@
+//Example 4.20
+//Convolution sum of x[n] and h[n]
+clc
+clear
+n1=0:5;
+n2=0:7;
+n3=0:12;
+a=0.8//assume the constant a=0.8
+for i=1:length(n1)
+ x(i)=1;
+end
+for j=1:length(n2)
+ h(j)=a^n2(j);
+end
+y=convol(x,h);
+subplot(3,1,1)
+xtitle("input signal x(n)","....................n","x[n]");
+plot(n1,x,'.');
+subplot(3,1,2)
+xtitle("system response h(n)","....................n","h[n]");
+plot(n2,h,'.');
+subplot(3,1,3)
+xtitle("output signal y(n)",".............................n","y[n]");
+plot(n3,y,'.');
diff --git a/2279/CH4/EX4.21/Ex4_21.sce b/2279/CH4/EX4.21/Ex4_21.sce
new file mode 100644
index 000000000..871235eee
--- /dev/null
+++ b/2279/CH4/EX4.21/Ex4_21.sce
@@ -0,0 +1,23 @@
+//Example 4.21
+//Convolution of x(t) and h(t)
+clc
+clear
+t1=0:0.01:5;
+t2=0:0.01:2;
+t3=0:0.01:7;
+for i=1:length(t1)
+ x(i)=1;
+end
+for j=1:length(t2)
+ h(j)=1;
+end
+y=convol(x,h);
+subplot(3,1,1)
+xtitle("input signal x(t)","....................t","x[t]");
+plot(t1,x);
+subplot(3,1,2)
+xtitle("system response h(t)","....................t","h[t]");
+plot(t2,h);
+subplot(3,1,3)
+xtitle("output signal y(t)",".............................t","y[t]");
+plot(t3,y);
diff --git a/2279/CH4/EX4.23/Ex4_23.sce b/2279/CH4/EX4.23/Ex4_23.sce
new file mode 100644
index 000000000..7e1724b52
--- /dev/null
+++ b/2279/CH4/EX4.23/Ex4_23.sce
@@ -0,0 +1,42 @@
+//Example 4.23
+//Convolution of x(t) and h(t)
+clc
+clear
+t1=0:0.01:20;
+t2=0:0.01:20;
+t3=0:0.01:40;
+a1=0.5;//constants a and b are equal
+b1=0.5;
+a2=0.8;// constants a and b are unequal
+b2=0.3;
+for i=1:length(t1)
+ x1(i)=exp(-a1*t1(i));
+ x2(i)=exp(-a2*t1(i));
+end
+for j=1:length(t2)
+ h1(j)=exp(-b1*t2(j));
+ h2(j)=exp(-b2*t2(j));
+end
+//case 1: a & b are equal
+y1=convol(x1,h1);
+subplot(3,1,1)
+xtitle("input signal x(t)","....................t","x[t]");
+plot(t1,x1);
+subplot(3,1,2)
+xtitle("system response h(t)","....................t","h[t]");
+plot(t2,h1);
+subplot(3,1,3)
+xtitle("output signal y(t)",".............................t","y[t]");
+plot(t3,y1);
+//case 2: a& b are unequal
+figure(1)
+y2=convol(x2,h2);
+subplot(3,1,1)
+xtitle("input signal x(t)","....................t","x[t]");
+plot(t1,x2);
+subplot(3,1,2)
+xtitle("system response h(t)","....................t","h[t]");
+plot(t2,h2);
+subplot(3,1,3)
+xtitle("output signal y(t)",".............................t","y[t]");
+plot(t3,y2);
diff --git a/2279/CH4/EX4.24/Ex4_24.sce b/2279/CH4/EX4.24/Ex4_24.sce
new file mode 100644
index 000000000..26e4ba5b7
--- /dev/null
+++ b/2279/CH4/EX4.24/Ex4_24.sce
@@ -0,0 +1,24 @@
+//Example 4.24
+//Convolution of x(t) and h(t)
+clc
+clear
+t1=-3:0.01:10;
+t2=1:0.01:10;
+t3=-2:0.01:20;
+a=0.5//assume a=0.5
+for i=1:length(t1)
+ x(i)=exp(-a*t1(i));
+end
+for j=1:length(t2)
+ h(j)=exp(-a*t2(j));
+end
+y=convol(x,h);
+subplot(3,1,1)
+xtitle("input signal x(t)","....................t","x[t]");
+plot(t1,x);
+subplot(3,1,2)
+xtitle("system response h(t)","....................t","h[t]");
+plot(t2,h);
+subplot(3,1,3)
+xtitle("output signal y(t)",".............................t","y[t]");
+plot(t3,y);
diff --git a/2279/CH4/EX4.26/Ex4_26.sce b/2279/CH4/EX4.26/Ex4_26.sce
new file mode 100644
index 000000000..0b55d5c1b
--- /dev/null
+++ b/2279/CH4/EX4.26/Ex4_26.sce
@@ -0,0 +1,52 @@
+//Interconnectiuion of LTI systems
+n=-10:10;
+for i=1:length(n)
+ if(n(i)==0)
+ h1(i)=2;
+ else
+ h1(i)=1;
+ end
+end
+for i=1:length(n)
+ if(n(i)==2)
+ h2(i)=1;
+ else
+ h2(i)=0;
+ end
+end
+for i=1:length(n)
+ if(n(i)>=1)
+ h3(i)=1;
+ else
+ h3(i)=0;
+end
+end
+for i=1:length(n)
+ if(n(i)>= -1)
+ h4(i)=1;
+ else
+ h4(i)=0;
+ end
+end
+for i=1:length(n)
+ h5(i)=n(i);
+ h6(i)=1;
+end
+h23=h2.*h3;
+h234=h4+h23;
+h1234=h1.*h234;
+h56=h5.*h6;
+h=h56+h1234;
+x=[1 -0.5];
+n1=[0 1];
+y=convol(x,h);
+n2=-10:11;
+subplot(3,1,1)
+xtitle("input signal x(n)","....................n","x[n]");
+plot(n1,x,'.');
+subplot(3,1,2)
+xtitle("system response h(n)","....................n","h[n]");
+plot(n,h,'.');
+subplot(3,1,3)
+xtitle("output signal y(n)",".............................n","y[n]");
+plot(n2,y,'.');
diff --git a/2279/CH4/EX4.27/Ex4_27.sce b/2279/CH4/EX4.27/Ex4_27.sce
new file mode 100644
index 000000000..a90807b05
--- /dev/null
+++ b/2279/CH4/EX4.27/Ex4_27.sce
@@ -0,0 +1,21 @@
+//Example 4.27
+//Interconnectiuion of LTI systems
+n2=0:18;
+h1=[1 5 10 11 8 4 1];
+h2=[1 1 zeros(1,5)];
+h3=[1 1 zeros(1,5)];
+a=convol(h1,h2);
+h=convol(a,h3);
+x=[1 -1];
+n1=[0 1];
+n3=0:19;
+y=convol(x,h);
+subplot(3,1,1)
+xtitle("input signal x(n)","....................n","x[n]");
+plot(n1,x,'.');
+subplot(3,1,2)
+xtitle("system response h(n)","....................n","h[n]");
+plot(n2,h,'.');
+subplot(3,1,3)
+xtitle("output signal y(n)",".............................n","y[n]");
+plot(n3,y,'.');
diff --git a/2279/CH4/EX4.30/Ex4_30.sce b/2279/CH4/EX4.30/Ex4_30.sce
new file mode 100644
index 000000000..83912f6d8
--- /dev/null
+++ b/2279/CH4/EX4.30/Ex4_30.sce
@@ -0,0 +1,33 @@
+//Example 4.30
+//Cascade connection of systems
+clc
+clear
+n=0:10;
+h11=[1 -0.5];
+for i=1:length(n)
+ h2(i)=0.5^n(i);
+ if (n(i)==0) then
+ h1(i)=1;
+ elseif n(i)==1 then
+ h1(i)=-0.5
+ else
+ h1(i)=0;
+ end
+end
+h=convol(h11,h2);
+n2=0:11;
+//assume x[n]=[1 1 1]
+n1=0:2;
+x=[1 1 1];
+n3=0:13;
+y=convol(x,h);
+subplot(3,1,1);
+plot(n1,x,'.');
+xtitle("Input Signal x[n]","n","x[n]")
+subplot(3,1,2);
+plot(n2,h,'.');
+xtitle("Impulse Response h[n]","n","h[n]")
+subplot(3,1,3);
+plot(n3,y,'.');
+xtitle("Output Signal y[n]","n","y[n]")
+disp("the given system is an invertible system");
diff --git a/2279/CH4/EX4.5/Ex4_5.sce b/2279/CH4/EX4.5/Ex4_5.sce
new file mode 100644
index 000000000..489ebefab
--- /dev/null
+++ b/2279/CH4/EX4.5/Ex4_5.sce
@@ -0,0 +1,20 @@
+//Example 4.5
+//Convolution sum of x[n] and h[n]
+clc
+clear
+n=0:2;
+n1=0:4;
+x=[0.5 0.5 0.5];
+h=[3 2 1];
+y=coeff(poly(h,'z','c')*poly(x,'z','c'))
+disp("Convolution of x[n] and h[n] is...")
+disp(y)
+subplot(3,1,1)
+xtitle("input signal x(n)","....................n","x[n]");
+plot(n,x,'.');
+subplot(3,1,2)
+xtitle("system response h(n)","....................n","h[n]");
+plot(n,h,'.');
+subplot(3,1,3)
+xtitle("output signal y(n)",".............................n","y[n]");
+plot(n1,y,'.');
diff --git a/2279/CH4/EX4.6/Ex4_6.sce b/2279/CH4/EX4.6/Ex4_6.sce
new file mode 100644
index 000000000..19f8fc8b6
--- /dev/null
+++ b/2279/CH4/EX4.6/Ex4_6.sce
@@ -0,0 +1,20 @@
+//Example 4.6
+//Convolution sum of x[n] and h[n]
+clc
+clear
+n=-1:1;
+n1=-2:2;
+x=[0.5 0.5 0.5];
+h=[3 2 1];
+y=coeff(poly(h,'z','c')*poly(x,'z','c'))
+disp("Convolution of x[n] and h[n] is...")
+disp(y)
+subplot(3,1,1)
+xtitle("input signal x(n)","....................n","x[n]");
+plot(n,x,'.');
+subplot(3,1,2)
+xtitle("system response h(n)","....................n","h[n]");
+plot(n,h,'.');
+subplot(3,1,3)
+xtitle("output signal y(n)",".............................n","y[n]");
+plot(n1,y,'.');
diff --git a/2279/CH5/EX5.1/Ex5_1.sce b/2279/CH5/EX5.1/Ex5_1.sce
new file mode 100644
index 000000000..cd9426dd7
--- /dev/null
+++ b/2279/CH5/EX5.1/Ex5_1.sce
@@ -0,0 +1,56 @@
+
+
+
+
+
+//Continuous Time Fourier Series Coefficients of
+//a periodic signal x(t) = sin(2*Wot)
+clear;
+close;
+clc;
+t = 0:0.01:1;
+T = 1;
+Wo = 2*%pi/T;
+xt = sin(2*Wo*t);
+for k =0:4
+ C(k+1,:) = exp(-sqrt(-1)*Wo*t.*k);
+ a(k+1) = xt*C(k+1,:)'/length(t);
+ if(abs(a(k+1))<=0.01)
+ a(k+1)=0;
+ end
+end
+a =a';
+ak = [-a,a(2:$)]
+for i=1:length(ak)
+ if real(ak(i))== 0 then
+ phase(i)=0;
+ else
+ if i<length(ak)/2 then
+ phase(i)= atan(imag(ak(i))/real(ak(i)));
+ else
+ phase(i)= -atan(imag(ak(i))/real(ak(i)));
+ end
+ end
+end
+disp("The fourier series coefficients are...")
+disp(ak)
+disp("magnitude of Fourier series coefficient")
+disp(abs(ak))
+disp("Phase of Fourier series coefficient in radians")
+disp(phase)
+n=-4:4;
+subplot(2,1,1)
+plot(n,abs(ak),'.');
+xtitle("|ak|","k","|ak|");
+subplot(2,1,2)
+for i=1:length(n)
+ if n(i)== -2 then
+ phase(i)=3.14/2;
+ elseif n(i)== 2 then
+ phase(i)= -3.14/2;
+ else
+ phase(i)=0;
+end
+end
+plot(n,phase,'.');
+xtitle("/_ak","k","/_ak");
diff --git a/2279/CH5/EX5.14/Ex5_14.sce b/2279/CH5/EX5.14/Ex5_14.sce
new file mode 100644
index 000000000..7aafaad98
--- /dev/null
+++ b/2279/CH5/EX5.14/Ex5_14.sce
@@ -0,0 +1,37 @@
+//Continuous Time Signal x(t)= exp(-B*t)u(t), t>0
+clear;
+clc;
+close;
+B =1;
+Dt = 0.005;
+t = 0:Dt:10;
+xt = exp(-B*t);
+Wmax = 2*%pi*1;
+K = 4;
+k = 0:(K/1000):K;
+W = k*Wmax/K;
+XW = xt* exp(-sqrt(-1)*t'*W) * Dt;
+XW_Mag = abs(XW);
+W = [-mtlb_fliplr(W), W(2:1001)];
+XW_Mag = [mtlb_fliplr(XW_Mag), XW_Mag(2:1001)];
+[XW_Phase,db] = phasemag(XW);
+XW_Phase = [-mtlb_fliplr(XW_Phase),XW_Phase(2:1001)];
+//Plotting Continuous Time Signal
+figure(1)
+plot(t,xt);
+xlabel('t in sec.');
+ylabel('x(t)')
+title('Continuous Time Signal')
+figure(2)
+//Plotting Magnitude Response of CTS
+subplot(2,1,1);
+plot(W,XW_Mag);
+xlabel('Frequency in Radians/Seconds---> W');
+ylabel('abs(X(jW))')
+title('Magnitude Response (CTFT)')
+//Plotting Phase Reponse of CTS
+subplot(2,1,2);
+plot(W,XW_Phase*%pi/180);
+xlabel(' Frequency in Radians/Seconds---> W');
+ylabel(' <X(jW)')
+title('Phase Response(CTFT) in Radians')
diff --git a/2279/CH5/EX5.15/Ex5_15.sce b/2279/CH5/EX5.15/Ex5_15.sce
new file mode 100644
index 000000000..fc0495da8
--- /dev/null
+++ b/2279/CH5/EX5.15/Ex5_15.sce
@@ -0,0 +1,37 @@
+//Continuous Time Signal x(t)= exp(B*t)u(-t), t>0
+clear;
+clc;
+close;
+B =1;
+Dt = 0.005;
+t = -10:Dt:0;
+xt = exp(B*t);
+Wmax = 2*%pi*1;
+K = 4;
+k = 0:(K/1000):K;
+W = k*Wmax/K;
+XW = xt* exp(-sqrt(-1)*t'*W) * Dt;
+XW_Mag = abs(XW);
+W = [-mtlb_fliplr(W), W(2:1001)];
+XW_Mag = [mtlb_fliplr(XW_Mag), XW_Mag(2:1001)];
+[XW_Phase,db] = phasemag(XW);
+XW_Phase = [-mtlb_fliplr(XW_Phase),XW_Phase(2:1001)];
+//Plotting Continuous Time Signal
+figure(1)
+plot(t,xt);
+xlabel('t in sec.');
+ylabel('x(t)')
+title('Continuous Time Signal')
+figure(2)
+//Plotting Magnitude Response of CTS
+subplot(2,1,1);
+plot(W,XW_Mag);
+xlabel('Frequency in Radians/Seconds---> W');
+ylabel('abs(X(jW))')
+title('Magnitude Response (CTFT)')
+//Plotting Phase Reponse of CTS
+subplot(2,1,2);
+plot(W,XW_Phase*%pi/180);
+xlabel(' Frequency in Radians/Seconds---> W');
+ylabel(' <X(jW)')
+title('Phase Response(CTFT) in Radians')
diff --git a/2279/CH5/EX5.16/Ex5_16.sce b/2279/CH5/EX5.16/Ex5_16.sce
new file mode 100644
index 000000000..39c8f4688
--- /dev/null
+++ b/2279/CH5/EX5.16/Ex5_16.sce
@@ -0,0 +1,27 @@
+//Continuous Time Signal x(t)= exp(-B*abs(t))
+clear;
+clc;
+close;
+B =1;
+Dt = 0.005;
+t = -4.5:Dt:4.5;
+xt = exp(-B*abs(t));
+Wmax = 2*%pi*1;
+K = 4;
+k = 0:(K/1000):K;
+W = k*Wmax/K;
+XW = xt* exp(-sqrt(-1)*t'*W) * Dt;
+XW = real(XW);
+W = [-mtlb_fliplr(W), W(2:1001)];
+XW = [mtlb_fliplr(XW), XW(2:1001)];
+disp("The given signal is even and it has no phase spectrum")
+subplot(2,1,1);
+plot(t,xt);
+xlabel('t in sec.');
+ylabel('x(t)')
+title('Continuous Time Signal')
+subplot(2,1,2);
+plot(W,XW);
+xlabel('Frequency in Radians/Seconds W');
+ylabel('X(jW)')
+title('Continuous-time Fourier Transform')
diff --git a/2279/CH5/EX5.17/Ex5_17.sce b/2279/CH5/EX5.17/Ex5_17.sce
new file mode 100644
index 000000000..7b7d4a03f
--- /dev/null
+++ b/2279/CH5/EX5.17/Ex5_17.sce
@@ -0,0 +1,29 @@
+//Frequency Response of a Rectangular Waveform
+// x(t)= A, from -T1 to T1
+clear;
+clc;
+close;
+A =1;
+Dt = 0.005;
+T1 = 4;
+t = -T1/2:Dt:T1/2;
+for i = 1:length(t)
+ xt(i) = A;
+end
+Wmax = 2*%pi*1;
+K = 4;
+k = 0:(K/1000):K;
+W = k*Wmax/K;
+xt = xt';
+XW = xt* exp(-sqrt(-1)*t'*W) * Dt;
+XW_Mag = real(XW);
+W = [-mtlb_fliplr(W), W(2:1001)];
+XW_Mag = [mtlb_fliplr(XW_Mag), XW_Mag(2:1001)];
+subplot(2,1,1);
+plot(t,xt);
+xlabel('t in sec.');
+title('Contiuous Time Signal x(t)')
+subplot(2,1,2);
+plot(W,XW_Mag);
+xlabel('Frequency in Radians/Seconds');
+title('Continuous-time Fourier Transform X(jW)')
diff --git a/2279/CH5/EX5.18/Ex5_18.sce b/2279/CH5/EX5.18/Ex5_18.sce
new file mode 100644
index 000000000..b57e4044c
--- /dev/null
+++ b/2279/CH5/EX5.18/Ex5_18.sce
@@ -0,0 +1,22 @@
+// Inverse Continuous Time Fourier Transform
+// X(jW)= 1, from -T1 to T1
+clear;
+clc;
+close;
+// CTFT
+A =1;
+Dw = 0.005;
+W1 = 4;
+w = -W1/2:Dw:W1/2;
+for i = 1:length(w)
+ XW(i) = A;
+end
+XW = XW';
+//Inverse Continuous-time Fourier Transform
+t = -3*%pi:%pi/length(w):3*%pi;
+xt =(1/(2*%pi))*XW *exp(sqrt(-1)*w'*t)*Dw;
+xt = real(xt);
+figure
+plot(t,xt);
+xlabel(' t Sec');
+title('Time domain signal x(t)')
diff --git a/2279/CH5/EX5.19/Ex5_19.sce b/2279/CH5/EX5.19/Ex5_19.sce
new file mode 100644
index 000000000..f61779753
--- /dev/null
+++ b/2279/CH5/EX5.19/Ex5_19.sce
@@ -0,0 +1,29 @@
+//frequency response of impulse signal
+clear;
+clc;
+close;
+A =1;
+Dt = 0.005;
+T1 = 4;
+Wo=2//Assume Wo=2
+t = -T1/2:Dt:T1/2;
+for i = 1:length(t)
+ xt(i)=sin(Wo*t(i));
+end
+Wmax = 2*%pi*1;
+K = 4;
+k = 0:(K/1000):K;
+W = k*Wmax/K;
+xt = xt';
+XW = xt* exp(-sqrt(-1)*t'*W) * Dt;
+XW_Mag = real(XW);
+W = [-mtlb_fliplr(W), W(2:1001)];
+XW_Mag = [mtlb_fliplr(XW_Mag), XW_Mag(2:1001)];
+subplot(2,1,1);
+plot(t,xt);
+xlabel('t in sec.');
+title('Contiuous Time Signal x(t)')
+subplot(2,1,2);
+plot(W,XW_Mag);
+xlabel('Frequency in Radians/Seconds');
+title('Continuous-time Fourier Transform X(jW)')
diff --git a/2279/CH5/EX5.2/Ex5_2.sce b/2279/CH5/EX5.2/Ex5_2.sce
new file mode 100644
index 000000000..f88b3868e
--- /dev/null
+++ b/2279/CH5/EX5.2/Ex5_2.sce
@@ -0,0 +1,43 @@
+//Continuous Time Fourier Series Coefficients of
+//a periodic signal x(t) = cos(Wot)
+clear;
+close;
+clc;
+t = 0:0.01:1;
+T = 1;
+Wo = 2*%pi/T;
+xt = cos(Wo*t);
+x1t=cos(Wo*-t);
+for k =0:2
+ C(k+1,:) = exp(-sqrt(-1)*Wo*t.*k);
+ a(k+1) = xt*C(k+1,:)'/length(t);
+ if(abs(a(k+1))<=0.01)
+ a(k+1)=0;
+ end
+end
+a =a';
+ak = [-a,a(2:$)]
+disp("The fourier series coefficients are...")
+disp(ak)
+disp("magnitude of Fourier series coefficient")
+disp(abs(ak))
+n=-2:2;
+subplot(2,1,1)
+plot(n,abs(ak),'.');
+xtitle("Magnitude Spectrum","k","|ak|");
+if xt== x1t then
+ disp("The Given signal is even. It has no phase spectrum");
+else
+for i=1:length(ak)
+ if real(ak(i))== 0 then
+ phase(i)=0;
+ else
+ phase(i)=atan(imag(ak(i))/real(ak(i)));
+ end
+end
+disp("Phase of Fourier series coefficient in radians")
+disp(phase)
+subplot(2,1,2)
+plot(n,phase,'.');
+xtitle("Phase Spectrum","k","ak in radians");
+end
diff --git a/2279/CH5/EX5.20/Ex5_20.sce b/2279/CH5/EX5.20/Ex5_20.sce
new file mode 100644
index 000000000..fc26d738c
--- /dev/null
+++ b/2279/CH5/EX5.20/Ex5_20.sce
@@ -0,0 +1,28 @@
+// Inverse Continuous Time Fourier Transform
+// X(jW)= 2*pi, at W=0
+clear;
+clc;
+close;
+// CTFT
+A =1;
+Dw = 0.005;
+W1 = 4;
+w = -W1/2:Dw:W1/2;
+for i = 1:length(w)
+ if w(i)==0 then
+ XW(i) = 2*%pi;
+else
+ XW(i)=0;
+end
+end
+XW = XW';
+subplot(2,1,1)
+plot(w,XW)
+//Inverse Continuous-time Fourier Transform
+t = -3*%pi:%pi/length(w):3*%pi;
+xt =(1/(2*%pi))*XW *exp(sqrt(-1)*w'*t)*Dw;
+xt = real(1+xt);
+subplot(2,1,2)
+plot(t,xt);
+xlabel(' t Sec');
+title('Time domain signal x(t)')
diff --git a/2279/CH5/EX5.21/Ex5_21.sce b/2279/CH5/EX5.21/Ex5_21.sce
new file mode 100644
index 000000000..f50d54b18
--- /dev/null
+++ b/2279/CH5/EX5.21/Ex5_21.sce
@@ -0,0 +1,26 @@
+// Inverse Continuous Time Fourier Transform
+// X(jW)= 2*pi, at W=Wo
+clear;
+clc;
+close;
+// CTFT
+A =1;
+Dw = 0.005;
+W1 = 4;
+Wo=2//Assume Wo=2
+w = -W1/2:Dw:W1/2;
+for i = 1:length(w)
+ if w(i)==Wo then
+ XW(i) = 2*%pi;
+else
+ XW(i)=0;
+end
+end
+XW = XW';
+//Inverse Continuous-time Fourier Transform
+t = -3*%pi:%pi/length(w):3*%pi;
+xt =(1/(2*%pi))*XW *exp(sqrt(-1)*w'*t)*Dw;
+xt = real(1+xt);
+plot(t,xt);
+xlabel(' t Sec');
+title('Time domain signal x(t)')
diff --git a/2279/CH5/EX5.22/Ex5_22.sce b/2279/CH5/EX5.22/Ex5_22.sce
new file mode 100644
index 000000000..af89d94f6
--- /dev/null
+++ b/2279/CH5/EX5.22/Ex5_22.sce
@@ -0,0 +1,26 @@
+// Inverse Continuous Time Fourier Transform
+// X(jW)= 2*pi, at W=-Wo
+clear;
+clc;
+close;
+// CTFT
+A =1;
+Dw = 0.005;
+W1 = 4;
+Wo=2//Assume Wo=2
+w = -W1/2:Dw:W1/2;
+for i = 1:length(w)
+ if w(i)==-Wo then
+ XW(i) = 2*%pi;
+else
+ XW(i)=0;
+end
+end
+XW = XW';
+//Inverse Continuous-time Fourier Transform
+t = -3*%pi:%pi/length(w):3*%pi;
+xt =(1/(2*%pi))*XW *exp(sqrt(-1)*w'*t)*Dw;
+xt = real(1+xt);
+plot(t,xt);
+xlabel(' t Sec');
+title('Time domain signal x(t)')
diff --git a/2279/CH5/EX5.24/Ex5_24.sce b/2279/CH5/EX5.24/Ex5_24.sce
new file mode 100644
index 000000000..cf324aad2
--- /dev/null
+++ b/2279/CH5/EX5.24/Ex5_24.sce
@@ -0,0 +1,14 @@
+// Continuous Time Fourier Transforms of
+// Sinusoidal waveforms sin(Wot)
+clear
+clc;
+close;
+T1 = 2;
+T = 4*T1;
+Wo = 2*%pi/T;
+W = [-Wo,0,Wo];
+ak = (2*%pi*Wo*T1/%pi)/sqrt(-1);
+XW = [-ak,0,ak];
+plot(W,-imag(XW),'.');
+xlabel(' W');
+xtitle('CTFT of sin(Wot)','W','X(jW)')
diff --git a/2279/CH5/EX5.25/Ex5_25.sce b/2279/CH5/EX5.25/Ex5_25.sce
new file mode 100644
index 000000000..350ed7339
--- /dev/null
+++ b/2279/CH5/EX5.25/Ex5_25.sce
@@ -0,0 +1,16 @@
+// Continuous Time Fourier Transforms of
+// Sinusoidal waveforms cos(Wot)
+clear;
+clc;
+close;
+// CTFT
+T1 = 2;
+T = 4*T1;
+Wo = 2*%pi/T;
+W = [-Wo,0,Wo];
+ak = (2*%pi*Wo*T1/%pi);
+XW =[ak,0,ak];
+plot(W,abs(XW),'.');
+xlabel(' W');
+xtitle('CTFT of cos(Wot)','W','X(jW)')
+
diff --git a/2279/CH5/EX5.3/Ex5_3.sce b/2279/CH5/EX5.3/Ex5_3.sce
new file mode 100644
index 000000000..f3de06d08
--- /dev/null
+++ b/2279/CH5/EX5.3/Ex5_3.sce
@@ -0,0 +1,34 @@
+//Continuous Time Fourier Series Coefficients of
+//a periodic signal x(t) = 5*cos((%pi/2*t)+(%pi/6))
+clear;
+close;
+clc;
+t = 0:0.01:1;
+T = 1;
+Wo = 2*%pi/T;
+xt = cos((%pi/2*t)+(%pi/6))
+x1t=cos((%pi/2*-t)+(%pi/6))
+
+//x(t) is expanded according to Euler's theorem
+x=5/2*(exp(%i*(%pi/2*t+%pi/6))+exp(-%i*(%pi/2*t+%pi/6)));
+a1=5/2*exp(%i*%pi/6);
+a_1=5/2*exp(-%i*%pi/6);
+ak=[zeros(1,5) a_1 0 a1 zeros(1,5)];
+k=-6:6;
+disp("The fourier series coefficients are...")
+disp(ak)
+disp("magnitude of Fourier series coefficient")
+disp(abs(ak))
+subplot(2,1,1)
+plot(k,abs(ak),'.');
+xtitle("Magnitude Spectrum","k","|ak|");
+if xt== x1t then
+ disp("The Given signal is even. It has no phase spectrum");
+else
+ phase=[zeros(1,5) atan(imag(a_1)/real(a_1)) 0 atan(imag(a1)/real(a1)) zeros(1,5)];
+ disp("Phase of Fourier series coefficient in radians")
+ disp(phase)
+ subplot(2,1,2)
+ plot(k,phase,'.');
+ xtitle("Phase Spectrum","k","ak in radians");
+end
diff --git a/2279/CH5/EX5.32/Ex5_32.sce b/2279/CH5/EX5.32/Ex5_32.sce
new file mode 100644
index 000000000..43cb6362a
--- /dev/null
+++ b/2279/CH5/EX5.32/Ex5_32.sce
@@ -0,0 +1,21 @@
+//CTFT of Periodic Impulse Train
+clear;
+clc;
+close;
+// CTFT
+T = -4:4;;
+T1 = 1;
+xt = ones(1,length(T));
+ak = 1/T1;
+XW = 2*%pi*ak*ones(1,length(T));
+Wo = 2*%pi/T1;
+W = Wo*T;
+figure
+subplot(2,1,1)
+plot2d3('gnn',T,xt);
+xlabel(' t');
+title('Periodic Impulse Train')
+subplot(2,1,2)
+plot2d3('gnn',W,XW);
+xlabel(' t');
+title('CTFT of Periodic Impulse Train')
diff --git a/2279/CH5/EX5.37/Ex5_37.sce b/2279/CH5/EX5.37/Ex5_37.sce
new file mode 100644
index 000000000..bc805dab7
--- /dev/null
+++ b/2279/CH5/EX5.37/Ex5_37.sce
@@ -0,0 +1,37 @@
+//Continuous Time Signal x(t)= 0.5*exp(-B*t*0.5)u(t), t>0
+clear;
+clc;
+close;
+B =1;
+Dt = 0.005;
+t = 0:Dt:10;
+h = 0.5*exp(-B*t*0.5);
+Wmax = 2*%pi*1;
+K = 4;
+k = 0:(K/1000):K;
+W = k*Wmax/K;
+XW = h* exp(-sqrt(-1)*t'*W) * Dt;
+XW_Mag = abs(XW);
+W = [-mtlb_fliplr(W), W(2:1001)];
+XW_Mag = [mtlb_fliplr(XW_Mag), XW_Mag(2:1001)];
+[XW_Phase,db] = phasemag(XW);
+XW_Phase = [-mtlb_fliplr(XW_Phase),XW_Phase(2:1001)];
+//Plotting Continuous Time Signal
+figure(1)
+plot(t,h);
+xlabel('t in sec.');
+ylabel('x(t)')
+title('Continuous Time Signal')
+figure(2)
+//Plotting Magnitude Response of CTS
+subplot(2,1,1);
+plot(W,XW_Mag);
+xlabel('Frequency in Radians/Seconds---> W');
+ylabel('abs(X(jW))')
+title('Magnitude Response (CTFT)')
+//Plotting Phase Reponse of CTS
+subplot(2,1,2);
+plot(W,XW_Phase*%pi/180);
+xlabel(' Frequency in Radians/Seconds---> W');
+ylabel(' <X(jW)')
+title('Phase Response(CTFT) in Radians')
diff --git a/2279/CH5/EX5.4/Ex5_4.sce b/2279/CH5/EX5.4/Ex5_4.sce
new file mode 100644
index 000000000..ee824c03f
--- /dev/null
+++ b/2279/CH5/EX5.4/Ex5_4.sce
@@ -0,0 +1,35 @@
+//Continuous Time Fourier Series Coefficients of
+//a periodic signal x(t) = 1+sin(6t)+cos(4t)
+clear;
+close;
+clc;
+t = 0:0.01:1;
+xt = 1+sin(6*t)+cos(4*t);
+x_t = 1+sin(6*-t)+cos(4*-t);
+
+//x(t) is expanded according to Euler's theorem
+x=1+(1/2)*exp(%i*4*t)+(1/2)*exp(-%i*4*t)+(1/(2*%i))*exp(%i*6*t)-(1/(2*%i))*exp(-%i*6*t);
+a0=1;
+a2=(1/2)
+a_2=(1/2)
+a3=(1/(2*%i));
+a_3=-(1/(2*%i));
+ak=[zeros(1,5) a_3 a_2 0 a2 a3 zeros(1,5)];
+k=-7:7;
+disp("The fourier series coefficients are...")
+disp(ak)
+disp("magnitude of Fourier series coefficient")
+disp(abs(ak))
+subplot(2,1,1)
+plot(k,abs(ak),'.');
+xtitle("Magnitude Spectrum","k","|ak|");
+if xt== x_t then
+ disp("The Given signal is even. It has no phase spectrum");
+else
+ phase=[zeros(1,6) %pi/2 0 -%pi/2 zeros(1,6)];
+ disp("Phase of Fourier series coefficient in radians")
+ disp(phase)
+ subplot(2,1,2)
+ plot(k,phase,'.');
+ xtitle("Phase Spectrum","k","ak in radians");
+end
diff --git a/2279/CH5/EX5.5/Ex5_5.sce b/2279/CH5/EX5.5/Ex5_5.sce
new file mode 100644
index 000000000..5f93e2cfb
--- /dev/null
+++ b/2279/CH5/EX5.5/Ex5_5.sce
@@ -0,0 +1,41 @@
+//Fourier Series coefficients of the signal x(t)
+//Assume the period of the signal T=10
+clc
+clear
+close
+T=1;
+To=1/4;
+//Assume the magnitude of the signal A=1
+A=1;
+t=-10:0.01:10;
+for i=1:length(t)
+ if t>To & t<-To then
+ x(i)=0;
+ else
+ x(i)=A;
+ end
+end
+
+Wo=2*%pi;
+
+k=-5:5
+for i=1:length(k)
+ if k(i)==0 then
+ ak(i)=1.5;
+ else
+ ak(i)=(sin(k(i)*%pi/2))/(k(i)*%pi);
+ end
+end
+
+disp("The fourier series coefficients are...")
+disp(ak)
+disp("magnitude of Fourier series coefficient")
+disp(abs(ak))
+disp("the givem signal is even and so it has no phase spectrum")
+//PLotting frequency spectrum
+subplot(2,1,2)
+plot(k,abs(ak),'.');
+xtitle("Magnitude Spectrum","k","|ak|");
+subplot(2,1,1)
+plot(k,ak,'.');
+xtitle("Ak","k","ak");
diff --git a/2279/CH5/EX5.6/Ex5_6.sce b/2279/CH5/EX5.6/Ex5_6.sce
new file mode 100644
index 000000000..a08627cd1
--- /dev/null
+++ b/2279/CH5/EX5.6/Ex5_6.sce
@@ -0,0 +1,21 @@
+//Fourier Series coefficients for Impulse train
+clc
+clear
+close
+//Assume period of the impulse train T=2
+T=2;
+t=-5*T:T:5*T;
+for i=1:length(t)
+ x(i)=1;
+end
+//Using sifting property of the impulse signal
+k=-10:10
+for i=1:length(k)
+ ak(i)=1/T;
+end
+subplot(2,1,1)
+plot(t,x,'.')
+xtitle("Impulse train","t","x(t)")
+subplot(2,1,2)
+plot(k,ak,'.')
+xtitle("Fourier coefficients of impulse train","k","ak")
diff --git a/2279/CH5/EX5.7/Ex5_7.sce b/2279/CH5/EX5.7/Ex5_7.sce
new file mode 100644
index 000000000..b1a9f8517
--- /dev/null
+++ b/2279/CH5/EX5.7/Ex5_7.sce
@@ -0,0 +1,50 @@
+//Fourier Series coefficients of half-wave rectifier output
+//Assume the period of the signal T=1
+t=-0.5:0.01:1;
+T = 1;
+for i=1:length(t)
+ if t(i)<T/2 then
+ x(i)=sin(2*%pi*t(i));
+ else
+ x(i)=0;
+ end
+end
+k=-10:10;
+for i=1:length(k)
+ if k(i)==1 then
+ ak(i)=1/(4*%i);
+ elseif k(i)==-1
+ ak(i)=-1/(4*%i);
+ else
+ ak(i)=(cos(k(i)*%pi/2)*exp(-k(i)*%pi/2*-%i))/(%pi-(%pi*k(i)*k(i)));
+ end
+end
+
+
+disp("The fourier series coefficients are...")
+disp(ak)
+disp("magnitude of Fourier series coefficient")
+disp(abs(ak))
+//PLotting frequency spectrum
+subplot(2,1,1)
+plot(k,abs(ak),'.');
+xtitle("Magnitude Spectrum","k","|ak|");
+for i=1:length(k)
+ if k(i)==0 | k(i)==3 | k(i)==-3 | k(i)==-5 |k(i)==5 then
+ phase(i)=0;
+ elseif k(i)==-1 then
+ phase(i)=%pi/2;
+ elseif k(i)==1 then
+ phase(i)=-%pi/2;
+ elseif k(i)==-2 | k(i)==-4
+ phase(i)=%pi;
+ elseif k(i)==2 | k(i)==4
+ phase(i)=-%pi;
+ else
+ phase(i) = 0;
+ end
+end
+subplot(2,1,2)
+plot(k,phase,'.');
+xtitle("Phase Spectrum","k","angle(ak)");
+disp(phase) \ No newline at end of file
diff --git a/2279/CH5/EX5.8/Ex5_8.sce b/2279/CH5/EX5.8/Ex5_8.sce
new file mode 100644
index 000000000..181ba1ef2
--- /dev/null
+++ b/2279/CH5/EX5.8/Ex5_8.sce
@@ -0,0 +1,23 @@
+//Fourier Series coefficients of half-wave rectifier output
+//Assume the period of the signal T=1
+t=-0.5:0.01:0.5;
+for i=1:length(t)
+ if t(i)<-0.25 & t(i)>0.25 then
+ x(i)=-1;
+ else
+ x(i)=1;
+ end
+end
+k=-10:10;
+for i=1:length(k)
+ if k(i)==0 then
+ ak(i)=0;
+ else
+ ak(i)=(%i*((2-(-1)^k(i))*exp(-%i*k(i)*%pi/2)-exp(%i*k(i)*%pi/2)))/(k(i)*2*%pi);
+ end
+end
+
+disp("The fourier series coefficients are...")
+disp(ak)
+plot(k,ak,'.')
+xtitle("Fourier Coefficients","k","ak")
diff --git a/2279/CH6/EX6.1/Ex6_1.sce b/2279/CH6/EX6.1/Ex6_1.sce
new file mode 100644
index 000000000..fd38eb38b
--- /dev/null
+++ b/2279/CH6/EX6.1/Ex6_1.sce
@@ -0,0 +1,27 @@
+//Sampling the CT signals
+clc
+clear
+close
+t=-0.3:0.0001:0.3;
+x1=2*cos(2*%pi*20*t);//F1=20Hz
+x2=2*cos(2*%pi*80*t);//F2=80Hz
+figure(1)
+subplot(2,1,1)
+plot(t,x1);
+xtitle("CT Signal X1(t)","t","x1(t)");
+subplot(2,1,2)
+plot(t,x2)
+xtitle("CT Signal X2(t)","t","x2(t)");
+//Given Sampling frequency Fs=60Hz
+Fs=60;
+n=-10:1:10;
+Ts=1/60;//Sampling interval Ts=1/Fs
+x1_n=2*cos(2*%pi*20*n*Ts);
+x2_n=2*cos(2*%pi*80*n*Ts);
+figure(2)
+subplot(2,1,1)
+plot2d3('gnn',n,x1_n,3);
+xtitle("Sampled signal x1[n]","n","x1[n]")
+subplot(2,1,2)
+plot2d3('gnn',n,x2_n,3);
+xtitle("Sampled signal x2[n]","n","x2[n]")
diff --git a/2279/CH6/EX6.2/Ex6_2.sce b/2279/CH6/EX6.2/Ex6_2.sce
new file mode 100644
index 000000000..ac8ea0186
--- /dev/null
+++ b/2279/CH6/EX6.2/Ex6_2.sce
@@ -0,0 +1,19 @@
+//Sampling the CT signals
+clc
+clear
+close
+t=-10:0.01:10;
+x=sin(%pi*t);
+figure(1)
+subplot(2,1,1)
+plot(t,x);
+xtitle("CT Signal sin(pi*t)","t","x(t)");
+Wb=%pi;//Given Sampling frequency is Pi radians
+Ws=2*Wb;
+Fs=Ws/(2*%pi);
+n=-100:1:100;
+Ts=1/Fs;//Sampling interval Ts=1/Fs
+x_n=sin(%pi*n*Ts);
+subplot(2,1,2)
+plot2d(n,x_n,rect=[-100 -2 100 2]);
+xtitle("Sampled signal x[n]","n","x[n]")
diff --git a/2279/CH6/EX6.3/Ex6_3.sce b/2279/CH6/EX6.3/Ex6_3.sce
new file mode 100644
index 000000000..00aaa64e7
--- /dev/null
+++ b/2279/CH6/EX6.3/Ex6_3.sce
@@ -0,0 +1,24 @@
+//Sampling the CT signals
+clc
+clear
+close
+t=-0.3:0.0001:0.3;
+x=5*sin(10*%pi*t);
+figure(1)
+plot(t,x);
+xtitle("CT Signal x(t)","t","x(t)");
+//Given Sampling frequency (a) Fs=15Hz (b) Fs=6Hz
+Fs1=15;
+Fs2=6;
+n=-10:1:10;
+Ts1=1/Fs1;//Sampling interval Ts=1/Fs
+Ts2=1/Fs2;
+x1=5*sin(%pi*10*n*Ts1);
+x2=5*sin(%pi*10*n*Ts2);
+figure(2)
+subplot(2,1,1)
+plot2d3('gnn',n,x1);
+xtitle("Sampled signal Fs=15Hz","n","x1[n]")
+subplot(2,1,2)
+plot2d3('gnn',n,x2);
+xtitle("Sampled signal Fs=6Hz","n","x2[n]")
diff --git a/2279/CH6/EX6.4/Ex6_4.sce b/2279/CH6/EX6.4/Ex6_4.sce
new file mode 100644
index 000000000..b049ab9ef
--- /dev/null
+++ b/2279/CH6/EX6.4/Ex6_4.sce
@@ -0,0 +1,41 @@
+// Continuous Time Fourier Transforms of
+// Sinusoidal waveforms 3cos(2*pi*t)
+clear;
+clc;
+close;
+// CTFT
+t=-10:0.01:10;
+x=3*cos(2*%pi*t);
+subplot(2,1,1)
+plot(t,x);
+xtitle("CT signal x(t)","t","x(t)");
+T1 = 2;
+T = 4*T1;
+Wo = 6*%pi/T;
+W = [-Wo,0,Wo];
+ak = (2*%pi*Wo*T1/%pi);
+XW =[ak,0,ak];
+subplot(2,1,2)
+plot2d3('gnn',W,real(XW));
+xlabel(' W');
+xtitle('CTFT of cos(Wot)','W','X(jW)')
+n=-10:10;
+W1=4*%pi;
+W2=8*%pi;
+W3=3*%pi;
+T1=(2*%pi)/W1;
+T2=(2*%pi)/W2;
+T3=(2*%pi)/W3;
+x1=3*cos(2*%pi*n*T1);
+x2=3*cos(2*%pi*n*T2);
+x3=3*cos(2*%pi*n*T3);
+figure(1)
+subplot(3,1,1)
+plot2d3('gnn',n,x1);
+xtitle("X(t) sampled at Ws=4*pi","n","x1[n]");
+subplot(3,1,2)
+plot2d3('gnn',n,x2);
+xtitle("X(t) sampled at Ws=8*pi","n","x2[n]");
+subplot(3,1,3)
+plot2d3('gnn',n,x3);
+xtitle("X(t) sampled at Ws=3*pi","n","x3[n]");
diff --git a/2279/CH6/EX6.6/Ex6_6.sce b/2279/CH6/EX6.6/Ex6_6.sce
new file mode 100644
index 000000000..6b952dc2a
--- /dev/null
+++ b/2279/CH6/EX6.6/Ex6_6.sce
@@ -0,0 +1,16 @@
+//Sampling the signal at nyquist rate
+clear;
+clc;
+close;
+t=-1:0.01:1;
+x=2*cos(200*%pi*t)+3*sin(100*%pi*t)-4*sin(500*%pi*t);
+f1=100;
+f2=50;
+f3=250;
+fb=max(f1,f2,f3);
+Fs=2*fb;
+Ts=1/Fs;
+n=-10:10;
+x_n=2*cos(200*%pi*n*Ts)+3*sin(100*%pi*n*Ts)-4*sin(500*%pi*n*Ts);
+plot2d3('gnn',n,x_n)
+xtitle("DT Signal x(n) sampled at nyquist rate","n","x[n]");
diff --git a/2279/CH6/EX6.7/Ex6_7.sce b/2279/CH6/EX6.7/Ex6_7.sce
new file mode 100644
index 000000000..082423ad3
--- /dev/null
+++ b/2279/CH6/EX6.7/Ex6_7.sce
@@ -0,0 +1,53 @@
+//Determining nyquist rate for the signals
+clc
+clear
+close
+Wb1=4*%pi;
+Wb2=10*%pi;
+Wbs=max(Wb1,Wb2);
+Ws=2*Wbs;
+//Bandlimited frequency doesnt change by Amplitude scaling
+//(a) 2*x1(t)
+Wa=2*Wb1
+disp("Wa=")
+disp(Wa)
+//Timing shifting doesnt affect the magnitude spectrum
+//(b) x1(t-1)
+Wb=2*Wb1
+disp("Wb=")
+disp(Wb)
+//Adding two band-limited spectrums will not sampling frequency
+//(c) 2*x1(t)+x1(t-1)
+Wc=2*Wb1
+disp("Wc=")
+disp(Wc)
+//Compressing time axis expands frequency axis by the same factor
+//(d) x2(2t)
+Wd=2*2*Wb2
+disp("Wd=")
+disp(Wd)
+//Expanding the time axis compresses the frequency axis by same factor
+//(e) x2(t/2)
+We=1/2*2*Wb2
+disp("We=")
+disp(We)
+//(f) x2(2t)+x2(t/2)
+Wf=max(Wd,We)
+disp("Wf=")
+disp(Wf)
+//x1(t)x2(t)
+Wg=2*(Wb1+Wb2)
+disp("Wg=")
+disp(Wg)
+//x1(t)*x2(t)
+Wh=2*min(Wb1,Wb2)
+disp("Wh=")
+disp(Wh)
+//x1(t)*cos(2*%pi*t)
+Wi=2*(Wb1+2*%pi)
+disp("Wi=")
+disp(Wi)
+//x1'(t)
+Wj=2*Wb1
+disp("Wj=")
+disp(Wj)
diff --git a/2279/CH7/EX7.1/eg_7_1.sce b/2279/CH7/EX7.1/eg_7_1.sce
new file mode 100644
index 000000000..eb966be47
--- /dev/null
+++ b/2279/CH7/EX7.1/eg_7_1.sce
@@ -0,0 +1,23 @@
+//DTFS of x[n] =sin(Won)
+clear;
+close;
+clc;
+n = 0:0.01:5;
+N = 6;
+Wo = 2*%pi/N;
+xn = sin(Wo*n);
+for k =0:N-2
+ C(k+1,:) = exp(-sqrt(-1)*Wo*n.*k);
+ a(k+1) = xn*C(k+1,:)'/length(n);
+ if(abs(a(k+1))<=0.1)
+ a(k+1)=0;
+ end
+end
+a =a'
+a_conj = conj(a);
+ak = [a_conj($:-1:1),a(2:$)]
+k = -(N-2):(N-2);
+plot2d3('gnn',k,-imag(ak),5)
+plot2d3('gnn',N+k,-imag(ak),5)
+plot2d3('gnn',-(N+k),-imag(ak($:-1:1)),5)
+xtitle('ak','k','ak')
diff --git a/2279/CH7/EX7.10/Ex7_10.sce b/2279/CH7/EX7.10/Ex7_10.sce
new file mode 100644
index 000000000..67708d051
--- /dev/null
+++ b/2279/CH7/EX7.10/Ex7_10.sce
@@ -0,0 +1,22 @@
+//x[n] = 0.5+0.5*cos(2*%pi/N)n
+clear;
+close;
+clc;
+N = 8;
+n = 0:0.01:N;
+Wo = 2*%pi/N;
+xn =0.5*ones(1,length(n))+0.5*cos(Wo*n);
+for k =0:N-2
+ C(k+1,:) = exp(-sqrt(-1)*Wo*n.*k);
+ a(k+1) = xn*C(k+1,:)'/length(n);
+ if(abs(a(k+1))<=0.1)
+ a(k+1)=0;
+ end
+end
+a =a';
+a_conj =conj(a);
+ak = [a_conj($:-1:1),a(2:$)];
+Mag_ak = abs(ak);
+k = -(N-2):(N-2);
+plot2d3('gnn',k,Mag_ak,5)
+xtitle('abs(ak)','k','ak')
diff --git a/2279/CH7/EX7.16/Ex7_16.sce b/2279/CH7/EX7.16/Ex7_16.sce
new file mode 100644
index 000000000..15079a5fb
--- /dev/null
+++ b/2279/CH7/EX7.16/Ex7_16.sce
@@ -0,0 +1,32 @@
+//Discrete Time Fourier Transform of discrete sequence
+//x[n]= (a^n).u[n], |a|<1
+clear;
+clc;
+close;
+a1 = 0.5;
+max_limit = 10;
+for n = 0:max_limit-1
+ x1(n+1) = (a1^n);
+end
+n = 0:max_limit-1;
+Wmax = 2*%pi;
+K = 4;
+k = 0:(K/1000):K;
+W = k*Wmax/K;
+x1 = x1';
+XW1 = x1* exp(-sqrt(-1)*n'*W);
+XW1_Mag = abs(XW1);
+W = [-mtlb_fliplr(W), W(2:1001)]; // Omega from -Wmax to Wmax
+XW1_Mag = 2.5*[mtlb_fliplr(XW1_Mag), XW1_Mag(2:1001)];
+[XW1_Phase,db] = phasemag(XW1);
+XW1_Phase = (1/30)*[-mtlb_fliplr(XW1_Phase),XW1_Phase(2:1001)];
+subplot(3,1,1);
+plot2d3('gnn',n,x1);
+xtitle('Discrete Time Sequence x[n]')
+subplot(3,1,2);
+plot2d(W,XW1_Mag);
+title('Magnitude Response abs(X(jW))')
+subplot(3,1,3);
+plot2d(W,XW1_Phase);
+title('Phase Response <(X(jW))')
+
diff --git a/2279/CH7/EX7.17/Ex7_17.sce b/2279/CH7/EX7.17/Ex7_17.sce
new file mode 100644
index 000000000..7a9b0c450
--- /dev/null
+++ b/2279/CH7/EX7.17/Ex7_17.sce
@@ -0,0 +1,32 @@
+//Discrete Time Fourier Transform of discrete sequence
+//x[n]= (a^n).u[-n], |a|>1
+clear;
+clc;
+close;
+a1 = 3;
+min_limit = -20;
+n = min_limit:0
+for i=1:length(n)
+ x1(i) = (a1^n(i));
+end
+Wmax = 2*%pi;
+K = 4;
+k = 0:(K/1000):K;
+W = k*Wmax/K;
+x1 = x1';
+XW1 = x1* exp(-sqrt(-1)*n'*W);
+XW1_Mag = abs(XW1);
+W = [-mtlb_fliplr(W), W(2:1001)]; // Omega from -Wmax to Wmax
+XW1_Mag = [mtlb_fliplr(XW1_Mag), XW1_Mag(2:1001)];
+[XW1_Phase,db] = phasemag(XW1);
+XW1_Phase = [-mtlb_fliplr(XW1_Phase),XW1_Phase(2:1001)];
+subplot(3,1,1);
+plot2d3('gnn',n,x1);
+xtitle('Discrete Time Sequence x[n]','n','x[n]')
+subplot(3,1,2);
+plot2d(W,XW1_Mag);
+xtitle('Magnitude Response abs(X(jW))','w','|X(jW)|')
+subplot(3,1,3);
+plot2d(W,XW1_Phase);
+xtitle('Phase Response <(X(jW))','w','<(X(jW))')
+
diff --git a/2279/CH7/EX7.18/Ex7_18.sce b/2279/CH7/EX7.18/Ex7_18.sce
new file mode 100644
index 000000000..de4954a80
--- /dev/null
+++ b/2279/CH7/EX7.18/Ex7_18.sce
@@ -0,0 +1,27 @@
+//Discrete Time Fourier Transform of
+//x[n]= (a^abs(n)) |a|<1
+clear;
+clc;
+close;
+// DTS Signal
+a = 0.5;
+max_limit = 10;
+n = -max_limit+1:max_limit-1;
+x = a^abs(n);
+// Discrete-time Fourier Transform
+Wmax = 2*%pi;
+K = 4;
+k = 0:(K/1000):K;
+W = k*Wmax/K;
+XW = x* exp(-sqrt(-1)*n'*W);
+XW_Mag = real(XW);
+W = [-mtlb_fliplr(W), W(2:1001)]; // Omega from -Wmax to Wmax
+XW_Mag = [mtlb_fliplr(XW_Mag), XW_Mag(2:1001)];
+//plot for abs(a)<1
+figure
+subplot(2,1,1);
+plot2d3('gnn',n,x);
+xtitle('Discrete Time Sequence x[n] for a>0','n','x[n]')
+subplot(2,1,2);
+plot2d(W,XW_Mag);
+xtitle('Discrete Time Fourier Transform X(exp(jW))','w','|X(exp(jW))|')
diff --git a/2279/CH7/EX7.19/Ex7_19.sce b/2279/CH7/EX7.19/Ex7_19.sce
new file mode 100644
index 000000000..8d2c2918c
--- /dev/null
+++ b/2279/CH7/EX7.19/Ex7_19.sce
@@ -0,0 +1,25 @@
+//Discrete Time Fourier Transform of
+//x[n]= 1 , abs(n)&lt;=M1
+clear;
+clc;
+close;
+// DTS Signal
+M1 = 2;
+n = -M1:M1;
+x = ones(1,length(n));
+Wmax = 2*%pi;
+K = 4;
+k = 0:(K/1000):K;
+W = k*Wmax/K;
+XW = x* exp(-sqrt(-1)*n'*W);
+XW_Mag = real(XW);
+W = [-mtlb_fliplr(W), W(2:1001)]; // Omega from -Wmax to Wmax
+XW_Mag = [mtlb_fliplr(XW_Mag), XW_Mag(2:1001)];
+//plot for abs(a)&lt;1
+figure
+subplot(2,1,1);
+plot2d3('gnn',n,x,2);
+xtitle('Discrete Time Sequence x[n]','n','x[n]')
+subplot(2,1,2);
+plot2d(W,XW_Mag);
+xtitle('Discrete Time Fourier Transform X(exp(jW))','w','|X(exp(jW))|') \ No newline at end of file
diff --git a/2279/CH7/EX7.24/Ex7_24.sce b/2279/CH7/EX7.24/Ex7_24.sce
new file mode 100644
index 000000000..c01faa4e7
--- /dev/null
+++ b/2279/CH7/EX7.24/Ex7_24.sce
@@ -0,0 +1,22 @@
+//Discrete Time Fourier Transform of
+// Periodic Impulse Train
+clear;
+clc;
+close;
+N = 5;
+N1 = -3*N:3*N;
+xn = [zeros(1,N-1),1];
+x = [1 xn xn xn xn xn xn];
+ak = 1/N;
+XW = 2*%pi*ak*ones(1,2*N);
+Wo = 2*%pi/N;
+n = -N:N-1;
+W = Wo*n;
+figure
+subplot(2,1,1)
+plot2d3('gnn',N1,x,2);
+xtitle('Periodic Impulse Train','n','x[n]')
+subplot(2,1,2)
+plot2d3('gnn',W,XW,2);
+xtitle('DTFT of Periodic Impulse Train','w','|X(exp(jw))|')
+disp(Wo)
diff --git a/2279/CH7/EX7.26/Ex7_26.sce b/2279/CH7/EX7.26/Ex7_26.sce
new file mode 100644
index 000000000..6aa35df4b
--- /dev/null
+++ b/2279/CH7/EX7.26/Ex7_26.sce
@@ -0,0 +1,36 @@
+//Discrete Time Fourier Transform of discrete sequence
+//x[n]= 1, n=2
+clear;
+clc;
+close;
+a1 = 1/8;
+max_limit = 10;
+for n = 0:max_limit-1
+ if n==2 then
+ x1(n+1) = 1;
+else
+ x1(n+1) = 0;
+end
+end
+n = 0:max_limit-1;
+Wmax = 2*%pi;
+K = 4;
+k = 0:(K/1000):K;
+W = k*Wmax/K;
+x1 = x1';
+XW1 = x1* exp(-sqrt(-1)*n'*W);
+XW1_Mag = abs(XW1);
+W = [-mtlb_fliplr(W), W(2:1001)]; // Omega from -Wmax to Wmax
+XW1_Mag = [mtlb_fliplr(XW1_Mag), XW1_Mag(2:1001)];
+[XW1_Phase,db] = phasemag(XW1);
+XW1_Phase = [-mtlb_fliplr(XW1_Phase),XW1_Phase(2:1001)];
+subplot(3,1,1);
+plot2d3('gnn',n,x1);
+xtitle('Discrete Time Sequence x[n]')
+subplot(3,1,2);
+plot2d(W,XW1_Mag);
+title('Magnitude Response abs(X(jW))')
+subplot(3,1,3);
+plot2d(W,XW1_Phase);
+title('Phase Response <(X(jW))')
+
diff --git a/2279/CH7/EX7.3/Ex7_3.sce b/2279/CH7/EX7.3/Ex7_3.sce
new file mode 100644
index 000000000..310d1b57c
--- /dev/null
+++ b/2279/CH7/EX7.3/Ex7_3.sce
@@ -0,0 +1,32 @@
+//DTFS of x[n] =2cos((pi/3)*n+(pi/6))
+clear;
+close;
+clc;
+n = -3:3;
+N = 6;
+Wo = 2*%pi/N;
+xn = 2*cos((%pi/3)*n+(%pi/6));
+//By euler's theorem X[n] can be represented
+x_n=exp(%i*(%pi*n/3)+%pi/6)+exp(-%i*(%pi*n/3)+%pi/6)
+for i=1:length(n)
+ if n(i)==1
+ a(i)=exp(%i*%pi/6);
+ elseif n(i)==-1
+ a(i)=exp(-%i*%pi/6);
+ else
+ a(i)=0;
+ end
+end
+for i=1:length(a)
+ if real(a(i))==0 then
+ phase(i)=0;
+ else
+ phase(i)=atan(imag(a(i))/real(a(i)));
+end
+end
+subplot(2,1,1)
+plot2d3('gnn',n,abs(a))
+xtitle("MAgnitude spectrum","k","|ak|")
+subplot(2,1,2)
+plot2d3('gnn',n,phase)
+xtitle("Phase spectrum","k","angle(ak)")
diff --git a/2279/CH7/EX7.4/Ex7_4.sce b/2279/CH7/EX7.4/Ex7_4.sce
new file mode 100644
index 000000000..85dbd8892
--- /dev/null
+++ b/2279/CH7/EX7.4/Ex7_4.sce
@@ -0,0 +1,30 @@
+//Fouries series representation of combinarion of signals
+//x[n]=1+sin(pi*n/2)+cos(%pi*n/4)
+clc
+clear
+close
+n=-3:3;
+x=1+sin(%pi*n/2)+cos(%pi*n/4);
+w1=%pi/2;
+w2=%pi/4;
+N1=2*%pi/w1;
+N2=2*%pi/w2;
+N=max(N1,N2);
+wo=2*%pi/N;
+//Expanding x[n] by Euler's theorem
+xn=1+0.5*exp(%i*wo*n)+0.5*exp(-%i*wo*n)-0.5*%i*exp(%i*2*wo*n)-0.5*%i*exp(-%i*2*wo*n);
+a0=1;
+a1=0.5;
+a_1=0.5;
+a2=1/2*%i;
+a_2=-1/2*%i;
+a=[a_2 a_1 a0 a1 a2];
+a1=[0 a 0];
+phase=[%pi/2 0 0 0 -%pi/2]
+phase=[0 phase 0]
+subplot(2,1,1)
+plot(n,abs(a1),'.')
+xtitle("magnitude spectrum","k","ak")
+subplot(2,1,2)
+plot(n,phase,'.')
+xtitle("Phase spectrum","k","ak")
diff --git a/2279/CH7/EX7.5/Ex7_5.sce b/2279/CH7/EX7.5/Ex7_5.sce
new file mode 100644
index 000000000..a1251bdb9
--- /dev/null
+++ b/2279/CH7/EX7.5/Ex7_5.sce
@@ -0,0 +1,23 @@
+//DTFS coefficients of periodic square wave
+clear;
+close;
+clc;
+N = 10;
+N1 = 2;
+Wo = 2*%pi/N;
+xn = ones(1,length(N));
+n = -(2*N1+1):(2*N1+1);
+a(1) = (2*N1+1)/N;
+for k =1:2*N1
+ a(k+1) = sin((2*%pi*k*(N1+0.5))/N)/sin(%pi*k/N);
+ a(k+1) = a(k+1)/N;
+ if(abs(a(k+1))<=0.1)
+ a(k+1) =0;
+ end
+end
+a =a';
+a_conj =conj(a);
+ak = [a_conj($:-1:1),a(2:$)];
+k = -2*N1:2*N1;
+plot2d3('gnn',k,abs(ak))
+xtitle('Magnitude spectrum','k','|ak|')
diff --git a/2279/CH7/EX7.6/Ex7_6.sce b/2279/CH7/EX7.6/Ex7_6.sce
new file mode 100644
index 000000000..c313d8a12
--- /dev/null
+++ b/2279/CH7/EX7.6/Ex7_6.sce
@@ -0,0 +1,23 @@
+//DTFS of a periodic sequence
+clc
+clear
+close
+n=-4:3;
+x=[0 1 2 3 0 1 2 3];
+N=4;
+k=0:3;;
+wo=2*%pi/N;
+a0=1.5;
+a1=-0.5+0.5*%i;
+a2=-0.5;
+a3=-0.5-0.5*%i;
+a=[a0,a1,a2,a3]
+for i=1:length(a)
+ phase(i)=atan(imag(a(i))/real(a(i)));
+end
+subplot(2,1,1)
+plot(k,abs(a),'.');
+xtitle("magnitude spectrum","k","ak");
+subplot(2,1,2)
+plot(k,phase,'.');
+xtitle("phase spectrum","k","ak");
diff --git a/2279/CH7/EX7.7/Ex7_7.sce b/2279/CH7/EX7.7/Ex7_7.sce
new file mode 100644
index 000000000..9e9508b5f
--- /dev/null
+++ b/2279/CH7/EX7.7/Ex7_7.sce
@@ -0,0 +1,23 @@
+//DTFS of discrete periodic signal
+clc
+clear
+close
+N=2//asume N=2
+n=-2*N:2*N
+for i=1:length(n)
+ if modulo(n(i),N)==0 then
+ x(i)=1;
+else
+ x(i)=0;
+end
+end
+subplot(2,1,1)
+plot(n,x,'.')
+xtitle("Input signal x[n]","n","x[n]");
+k=-5:5;
+for i=1:length(k)
+ ak(i)=1/N;
+end
+subplot(2,1,2)
+plot(k,ak,'.')
+xtitle("Frequency spectrum","k","ak")
diff --git a/2279/CH7/EX7.8/Ex7_8.sce b/2279/CH7/EX7.8/Ex7_8.sce
new file mode 100644
index 000000000..5257de458
--- /dev/null
+++ b/2279/CH7/EX7.8/Ex7_8.sce
@@ -0,0 +1,31 @@
+//x[n] = 1+sin(2*%pi/N)n+3cos(2*%pi/N)n+cos[(4*%pi/N)n+%pi/4]
+clear;
+close;
+clc;
+N = 10;
+n = 0:0.01:N;
+Wo = 2*%pi/N;
+xn =ones(1,length(n))+sin(Wo*n)+3*cos(Wo*n)+cos(2*Wo*n+%pi/4);
+for k =0:N-2
+ C(k+1,:) = exp(-sqrt(-1)*Wo*n.*k);
+ a(k+1) = xn*C(k+1,:)'/length(n);
+ if(abs(a(k+1))<=0.1)
+ a(k+1)=0;
+ end
+end
+a =a';
+a_conj =conj(a);
+ak = [a_conj($:-1:1),a(2:$)];
+Mag_ak = abs(ak);
+for i = 1:length(a)
+ Phase_ak(i) = atan(imag(ak(i))/(real(ak(i))+0.0001));
+end
+Phase_ak = Phase_ak'
+Phase_ak = [Phase_ak(1:$-1) -Phase_ak($:-1:1)];
+k = -(N-2):(N-2);
+subplot(2,1,1)
+plot2d3('gnn',k,Mag_ak,5)
+xtitle('abs(ak)','k','ak')
+subplot(2,1,2)
+plot2d3('gnn',k,Phase_ak,5)
+xtitle('phase(ak)','k','ak')
diff --git a/2279/CH7/EX7.9/Ex7_9.sce b/2279/CH7/EX7.9/Ex7_9.sce
new file mode 100644
index 000000000..4f139a77f
--- /dev/null
+++ b/2279/CH7/EX7.9/Ex7_9.sce
@@ -0,0 +1,31 @@
+//x[n] = 1+sin(4*%pi/N)n+cos(10*%pi/N)n
+clear;
+close;
+clc;
+N = 21;
+n = 0:0.01:N;
+Wo = 2*%pi/N;
+xn =ones(1,length(n))+sin(2*Wo*n)+cos(5*Wo*n);
+for k =0:N-2
+ C(k+1,:) = exp(-sqrt(-1)*Wo*n.*k);
+ a(k+1) = xn*C(k+1,:)'/length(n);
+ if(abs(a(k+1))<=0.1)
+ a(k+1)=0;
+ end
+end
+a =a';
+a_conj =conj(a);
+ak = [a_conj($:-1:1),a(2:$)];
+Mag_ak = abs(ak);
+for i = 1:length(a)
+ Phase_ak(i) = atan(imag(ak(i))/(real(ak(i))+0.0001));
+end
+Phase_ak = Phase_ak'
+Phase_ak = [Phase_ak(1:$-1) -Phase_ak($:-1:1)];
+k = -(N-2):(N-2);
+subplot(2,1,1)
+plot2d3('gnn',k,Mag_ak,5)
+xtitle('abs(ak)','k','ak')
+subplot(2,1,2)
+plot2d3('gnn',k,Phase_ak,5)
+xtitle('phase(ak)','k','ak')