Humboldt-Universität zu Berlin - Faculty of Mathematics and Natural Sciences - Strukturforschung / Elektronenmikroskopie

fwhm1.txt

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% A sinple function for determining the full width at half maximum
% Input:
% x: the array of x-values
% f: the array of function values
% Output:
% fwhm: FWHM of f in the scale given by x
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
function FWHM = fwhm(x,f)
if nargin < 2
f = x;
x=[1:length(f)];
end
f1 = f-0.5*max(f);
ind = find(f1(1:end-1).*f1(2:end) <=0);
FWHM = x(ind(2))-x(ind(1));