function [w,bins] = scott(c,normal,factor);
% function [w,bins] = scott(c,normal,factor);
% Calculate bins width and bins vector using the Scott's rule applied to vector c
% normal = 1 : Use Normal rule
% normal = 0 : Use Correct normal rule with skewness factor
% factor : Multiply calculated width by factor

% Copyright (c) 2004-2006 Alessio Botta, Alberto Dainotti, Antonio Pescapè
% Email: {a.botta , alberto , pescape }@unina.it
% DIS - Dipartimento di Informatica e Sistemistica 
% University of Napoli Federico II, ITALY
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if nargin < 3
	factor = 1;
end
if nargin < 2
	normal = 1;
end

% Compute bins width by Scott's rule 
w = 3.49 * std(c) * length(c)^(-1/3);

if normal ~= 1
	% Distribution in lognormal-like
	s = std(log10(c));
	skew = (2^(1/3) * s) / ( exp(5/4*s^2) * (s^2 + 2)^(1/3) * (exp(s^2)-1)^(1/2) );
	clear s;
	fprintf('Skewness factor: %d (inverse: %d)\n', skew, 1/skew);
	w = w * skew;
end	

w = w * factor;

% Establish bins vector
bins = (min(c)+w/2):w:max(c);