26 lines
738 B
Matlab
26 lines
738 B
Matlab
function [ret] = find_nk_fit(~,VParams)
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Lz = 20;
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Nz = 4000;
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normfac = Lz/Nz;
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z = linspace(-0.5*Lz,0.5*Lz-Lz/Nz,Nz);
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dz = abs(z(2)-z(1));
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Kmax = pi*Nz/Lz;
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kz = linspace(-Kmax,Kmax,Nz+1);
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kz = kz(1:end-1);
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psiz = exp(-0.5*(abs(z)/VParams.ell).^VParams.nu);% VParams.nu
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normz = sum(abs(psiz).^2)*dz;
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psiz = psiz / sqrt(normz);
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psik = fftn(psiz)*normfac/(sqrt(2*pi)); % fftshifted
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nk = abs(psik).^2;
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nk_forfit = ifftshift(nk);
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f = fit(kz',nk_forfit','gauss1'); % f(x) = a1*exp(-((x-b1)/c1)^2)
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ret.ell = VParams.ell;
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ret.nu = VParams.nu;
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ret.ell_eff = 1/f.c1;
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end |