Add a useful package (from Source forge) for octave

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

diff --git a/octave_packages/nan-2.5.5/mad.m b/octave_packages/nan-2.5.5/mad.m
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+++ b/octave_packages/nan-2.5.5/mad.m
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+function R = mad(i,DIM)
+% MAD estimates the Mean Absolute deviation
+% (note that according to [1,2] this is the mean deviation; 
+% not the mean absolute deviation)
+%
+% y = mad(x,DIM)
+%   calculates the mean deviation of x in dimension DIM
+%
+% DIM  dimension
+%      1: STATS of columns
+%      2: STATS of rows
+%      default or []: first DIMENSION, with more than 1 element
+%
+% features:
+% - can deal with NaN's (missing values)
+% - dimension argument 
+% - compatible to Matlab and Octave
+%
+% see also: SUMSKIPNAN, VAR, STD, 
+%
+% REFERENCE(S):
+% [1] http://mathworld.wolfram.com/MeanDeviation.html
+% [2] L. Sachs, "Applied Statistics: A Handbook of Techniques", Springer-Verlag, 1984, page 253.
+%
+% [3] http://mathworld.wolfram.com/MeanAbsoluteDeviation.html
+% [4] Kenney, J. F. and Keeping, E. S. "Mean Absolute Deviation." §6.4 in Mathematics of Statistics, Pt. 1, 3rd ed. Princeton, NJ: Van Nostrand, pp. 76-77 1962. 
+
+%      $Id: mad.m 8223 2011-04-20 09:16:06Z schloegl $
+%      Copyright (C) 2000-2002,2010 by Alois Schloegl <alois.schloegl@gmail.com>
+%      This is part of the NaN-toolbox. For more details see
+%       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 2 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 nargin==1,
+        DIM = find(size(i)>1,1);
+        if isempty(DIM), DIM=1; end;
+end;
+
+
+[S,N] = sumskipnan(i,DIM);             % sum
+i     = i - repmat(S./N,size(i)./size(S));             % remove mean
+[S,N] = sumskipnan(abs(i),DIM);                % 
+
+%if flag_implicit_unbiased_estim;    %% ------- unbiased estimates ----------- 
+    n1         = max(N-1,0);                   % in case of n=0 and n=1, the (biased) variance, STD and STE are INF
+%else
+%    n1        = N;
+%end;
+
+R     = S./n1;
+
+