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close all
clear all
x = 0:0.01:500;
ez = 768*x.^3.*exp(-2*x)-90;
subplot(2, 2, 1);
plot(x(1:1000),ez(1:1000));
xlabel('Position (mm)');
ylabel('Potential (mV)');
sigmai = 1.010; %S/m
d = 55e-3; % mm
im=-(4608*x - 9216*x.^2 + 3072*x.^3).*exp(-2*x) * sigmai * pi * d^2 / 4;
subplot(2, 2, 2);
plot(x(1:1000),im(1:1000));
xlabel('Position (mm)');
ylabel('Current (mA/m)');
z0 = 150;
y0 = 20;
w = 1./sqrt((x-z0).^2 + 5*y0^2) / (4 * pi * 0.063);
%subplot(2, 2, 3);
%plot(x,w);
IM = fft(im);
W = fft(w);
mp = ifft(W .* IM);
subplot(2, 2, 3);
plot(x(1:50000),mp(1:50000)*1000);
ylim([-0.5 1.5]);
xlabel('Position (mm)');
ylabel('Potential (uV)');