Add a useful package (from Source forge) for octave

[CreaPhase.git] / octave_packages / nan-2.5.5 / ecdf.m

diff --git a/octave_packages/nan-2.5.5/ecdf.m b/octave_packages/nan-2.5.5/ecdf.m
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+++ b/octave_packages/nan-2.5.5/ecdf.m
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+function [F,X]=ecdf(h,Y)
+% ECDF empirical cumulative function  
+%  NaN's are considered Missing values and are ignored. 
+%
+%  [F,X] = ecdf(Y)
+%      calculates empirical cumulative distribution functions (i.e Kaplan-Meier estimate)
+%  ecdf(Y)
+%  ecdf(gca,Y)
+%      without output arguments plots the empirical cdf, in axis gca. 
+%
+% Y    input data
+%      must be a vector or matrix, in case Y is a matrix, the ecdf for every column is computed. 
+%
+% see also: HISTO2, HISTO3, PERCENTILE, QUANTILE
+
+
+%      $Id: ecdf.m 8223 2011-04-20 09:16:06Z schloegl $
+%      Copyright (C) 2009,2010 by Alois Schloegl <alois.schloegl@gmail.com>    
+%       This function is part of the NaN-toolbox
+%       http://pub.ist.ac.at/~schloegl/matlab/NaN/
+
+%    This program is free software; you can redistribute it and/or modify
+%    it under the terms of the GNU General Public License as published by
+%    the Free Software Foundation; either version 3 of the License, or
+%    (at your option) any later version.
+%
+%    This program is distributed in the hope that it will be useful,
+%    but WITHOUT ANY WARRANTY; without even the implied warranty of
+%    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+%    GNU General Public License for more details.
+%
+%    You should have received a copy of the GNU General Public License
+%    along with this program; If not, see <http://www.gnu.org/licenses/>.
+
+if ~isscalar(h) || ~ishandle(h) || isstruct(h),
+       Y = h; 
+       h = []; 
+end;   
+
+DIM = [];
+
+        SW = isstruct(Y);
+        if SW, SW = isfield(Y,'datatype'); end;
+        if SW, SW = strcmp(Y.datatype,'HISTOGRAM'); end;
+       if SW,                 
+                [yr,yc]=size(Y.H);
+                if ~isfield(Y,'N');
+                        Y.N = sum(Y.H,1);
+                end;
+               f = [zeros(1,yc);cumsum(Y.H,1)];
+               for k=1:yc,
+                       f(:,k)=f(:,k)/Y.N(k); 
+               end;            
+               t = [Y.X(1,:);Y.X]; 
+
+        elseif isnumeric(Y),
+               sz = size(Y);
+               if isempty(DIM),
+                       DIM = min(find(sz>1));
+                       if isempty(DIM), DIM = 1; end;
+               end;
+               if DIM==2, Y=Y.'; DIM = 1; end;         
+               
+               t = sort(Y,1); 
+               t = [t(1,:);t];         
+               N = sum(~isnan(Y),1); 
+                f = zeros(size(Y,1)+1,size(Y,2));
+               for k=1:size(Y,2),
+                       f(:,k)=[0:size(Y,1)]'/N(k); 
+               end;            
+       end; 
+       
+       if nargout<1, 
+               if  ~isempty(h), axes(h); end; 
+               stairs(t,f);
+       else 
+               F = f;
+               X = t;  
+       end;                    
+