function aFit = fitTwoSlit(xData,yData)

load twoSlit
a0 = 4;+
aFit = lsqcurvefit(@TwoSlitInter,a0,xData,yData);
plot(xData, yData, 'bo', xData, aFit, 'k-');
end

function Inten = TwoSlitInter(a,x)


L = 1025.; % Length in mm
lambda_l = 6.7e-4; %laser lambda in mm
k_l = 9.378e+03;   % k for laser in 1/mm
phi = k_l*a(2)*sin(abs(x-a(4))/L);
psi = k_l*a(3)*sin(abs(x-a(4))/L);

Inten = a(1)*(sin(phi/2)./(phi/2)).^2.*(cos(psi/2)).^2;

end