Matlab graphs not showing

Below are my codes

n      = 5*10e12;
vf     = 1.0*10e6;
mo     = 9.109*10e-31;
m      = 0.44*mo;
tau    = 10e-12;
e      = 1; %1.6022e-19;
E0     = 10; % Unit in KV/m
s      = 3.5*10e3;
hBar   = 1; %6.52*10e-16;
Ed     = 50;
Eo     = 8.85*10-12;
B      = [0.1, 0.2, 0.3]; % Unit in Tesla
W      = linspace(0,10, 101); % However many you want.
k      = W./s;
a0     = (2*pi*(hBar^2)*Eo)/m/e^2;
s0     = ((e^2)*n*tau)/m;
jo     = 1./(e*n*vf);

[L]   = meshgrid(-10000:200:10000);  % 1:0.1:3 span for 'q'
legendStrings = cell(length(B), 1);
for k1 = 1:length(B)
	thisN = B(k1);
    Wc = ((e.*thisN)./m);
    g  = 1 + (1i.*Wc.*tau); gstar = 1 - (1i.*Wc.*tau);
    BF = repmat(((k.*vf)./Wc),101,1);
	for i = 1:length(W)
        R = (L.*(besselj(L,BF).^2))./(1-1i.*(W(i)-(L.*Wc)).*tau);
        Rx = ((Wc./k).*sum(R(:)));
        Sx = ((L.*besselj(L,BF)).^2)./(1-1i.*(W(i)-(L.*Wc)).*tau);
        Sxx = ((2*s0)./(BF.^2)).*sum(Sx(:));
        gkw = 1+(1i.*(1./(Eo*(Ed+1))).*(Sxx./(s - Rx)));
        J = besselj(L,BF)./(1-1i.*(W(i)-(L.*Wc)).*tau).*(L+((k.*a0.*Sxx)./(Wc.*tau)./(Eo.*(s-Rx)))).*((g.*(L+1).*besselj(L+1,BF))+(gstar.*(L-1).*besselj(L-1,BF)));
        Jx = jo.*((abs((s0*E0)./gkw)).^2).*(1./(BF.^2)./(1+(Wc.*tau).^2)).*sum(J(:));
  end

	legendStrings{k1} = sprintf('B = %.3f', thisN);
	plot(W, real(Jx), '-', 'LineWidth', 2, 'MarkerSize', 15);
	hold on;
	drawnow;
end

grid on;
fontSize = 15;
xlabel('\omega (ns^{-1})', 'FontSize', fontSize)
ylabel('\it j_{x} (\mu A/m)', 'FontSize', fontSize)
title('\it j_{x} (\mu A/m) vs. \omega (ns^{-1}) ', 'FontSize', fontSize)
legend(legendStrings, 'Location', 'Best')

Answer 1

[maiaL]

Nothing is plotted because Jx is all NaN's, so something is wrong with your calculations.

[maiaL]

I don't know what this script is about, seems to be something with eletric/electromagnetic fields. But upon a quick inspection, the source of the NaN's is from divisions by zero in line 29:

Sxx = ((2*s0)./(BF.^2)).*sum(Sx(:));

The first column of BF are zeros, so you have some divisions by zero there.

[Samuel Suakye]

Plotting this equation numerically so I used meshgrid

[maiaL]

Can't help you with the math. The plot part of the script looks alright. It's just that what you're trying to plot are NaN's.

[Samuel Suakye]

Is there any way to plot this numerically ... because of the summation?

[maiaL]

I dont understand what you're asking.

[Samuel Suakye]

I used grid to plot those equations numerically. And am asking whether there is another way to plot same equations using vectors numerically