This shows how to print value of Ein in each iteration using OutputFcn
clc
close all
clear all
gam = 10e-3; % damping frequency
f = 8.8e-3; % oscillator strength
eb = 11.2; % background epsilon
x = 5.0; %constant
om = 1.5; % frequency array;%frequency array om=1.4:0.001:1.6
syms hw0 k wp Ein er
V = [hw0, k ,wp, Ein, er ];
eq1=hw0 - 1i*((gam+sqrt(-(gam*gam)-(4*k*k)))/(2)); % resonant frequency
eq2=k - sqrt((wp*wp)/(1+2*eb) ); %to find resonant frequency
eq3=wp - sqrt(hw0^2+x*Ein*Ein);%plasma frequency
eq4=Ein - (eb-er)/(er+2*eb);%internal electric field
eq5=er - 1- ( ( f * wp*wp )./ (hw0*hw0-om.*om-1i.*om*gam));%reletive permittivity
eqs = matlabFunction([eq1;eq2;eq3;eq4;eq5], 'Vars', {[hw0 k wp Ein er ].'});
initialguess=[1.5; 2.5 ;1.4; 0.436 - 1i*0.00000112 ; -16.5-1i*1.06 ];
options = optimoptions('fsolve','Display','none', 'OutputFcn', @outFcn, 'PlotFcn',@optimplotfirstorderopt,'MaxFunctionEvaluations',100);
sol=fsolve(eqs,initialguess,options);
hw0=sol(1);
k=sol(2);
wp=sol(3);
Ein=sol(4);
er=sol(5);
function y = outFcn(x, ~, s)
if strcmp(s, 'iter') % only print value when the current iteration finishes
fprintf('Ein=%f\n', x(4));
end
y = 0;
end
