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2 files changed, 33 insertions, 26 deletions

diff --git a/Part 2/RK4second.m b/Part 2/RK4second.m
index c5403f5..065665f 100644
--- a/Part 2/RK4second.m
+++ b/Part 2/RK4second.m
@@ -1,11 +1,11 @@
-function [qc_next,qc_dash_next] = RK4second(t,qc,qc_dash,h,func1,func2)

+function [xnext, ynext] = RK4second(t, x, y, h, f1, f2)

     %source from http://www.mymathlib.com/diffeq/runge-kutta/runge_kutta_3_8.html

-    k1 = func2(t,qc,qc_dash);

-    k2 = func2(t,qc + h/3, qc_dash + h*k1/3);

-    k3 = func2(t,qc + 2*h/3, qc_dash - h*k1/3 + h*k2);

-    k4 = func2(t,qc + h,qc_dash + h*k1 - h*k2 + h*k3);

+    ky1 = f2(t, x, y);

+    ky2 = f2(t, x + h/3, y + h*ky1/3);

+    ky3 = f2(t, x + 2*h/3, y - h*ky1/3 + h*ky2);

+    ky4 = f2(t, x + h, y + h*ky1 - h*ky2 + h*ky3);

     %yi+1 = yi + 1/8 ( k1 + 3 k2 + 3 k3 + k4 )

     %xi = x0 + i h

-    qc_next = qc + h*func1(t, qc, qc_dash);

-    qc_dash_next = qc_dash + h/8*(k1 + 3*k2 + 3*k3 + k4);

-end
\ No newline at end of file
+    xnext = x + h*f1(t, x, y);

+    ynext = y + h/8*(ky1 + 3*ky2 + 3*ky3 + ky4);

+end

diff --git a/Part 2/RLC_script.m b/Part 2/RLC_script.m
index 73977bc..881d941 100644
--- a/Part 2/RLC_script.m
+++ b/Part 2/RLC_script.m
@@ -1,38 +1,45 @@
-function RLC_script(f,h)

+function RLC_script (tf) 

+

 %initailise the circuits 

-R = 280;

-L = 600*10^(-3);

-C = 3*60^(-6);

-tf = 1/f;

-N = round(tf/h,0);

+R = 250;

+L = 650*10^(-3);

+C = 3*10^(-6);

+h = 0.00001; %step size

+

+%initailise the container 

 

-qc_dash = zeros(1,N);

-qc = zeros(1,N);

-t = zeros(1,N);

-Vout = zeros(1,N);

+N = round(tf/h); %number of iterations

+qc = zeros(1, N); %x

+qc_dash = zeros(1, N); %y  

+t = zeros(1, N);

+Vout = zeros(1, N);

 

 %input voltage

-Vin = @(t)5;

+% step function of 5 volt

+Vin = @(t)5*heaviside(t); 

+%Vin = @(t)

 

 %the coupled equation

-func1 = @(t,qc,qc_dash)qc_dash;

-func2 = @(t,qc,qc_dash)(Vin(t) - qc/C - R*qc_dash) / L;

+func1 = @(t, qc, qc_dash)qc_dash; 

+func2 = @(t, qc, qc_dash)(Vin(t) - qc/C - R*qc_dash)/L; 

 

 %the initial condition

+qc_dash(1) = 0; 

+qc(1) = 500*(10.^-9); 

 t(1) = 0;

-qc(1) = 500*10^(-9);

-qc_dash(1) = 0;

 

 %Rouge Kutta

-for i = 1 : N -1

-    [qc(i+1),qc_dash(i+1)] = RK4second(t(i),qc(i),qc_dash(i),h,func1,func2);

+for i = 1 : N - 1

     t(i + 1) = t(i) + h;

+    [qc(i + 1), qc_dash(i + 1)] = RK4second(t(i), qc(i), qc_dash(i), h, func1, func2); 

     Vout(i) = R*qc_dash(i);

 end

 

 %plot

+

 plot(Vout);

 xlabel('Time');

 ylabel('Amplitude');

-

 end

+

+