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−## Copyright (C) 2012 Rik Wehbring
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−## Copyright (C) 1995-2012 Kurt Hornik
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−##
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−## This file is part of Octave.
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−##
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−## Octave is free software; you can redistribute it and/or modify it
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−## under the terms of the GNU General Public License as published by
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−## the Free Software Foundation; either version 3 of the License, or (at
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−## your option) any later version.
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−##
+
−## Octave is distributed in the hope that it will be useful, but
+
−## WITHOUT ANY WARRANTY; without even the implied warranty of
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−## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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−## General Public License for more details.
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−##
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−## You should have received a copy of the GNU General Public License
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−## along with Octave; see the file COPYING.  If not, see
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−## <http://www.gnu.org/licenses/>.
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−
+
−## -*- texinfo -*-
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−## @deftypefn  {Function File} {} logistic_rnd (@var{r})
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−## @deftypefnx {Function File} {} logistic_rnd (@var{r}, @var{c}, @dots{})
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−## @deftypefnx {Function File} {} logistic_rnd ([@var{sz}])
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−## Return a matrix of random samples from the logistic distribution.
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−##
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−## When called with a single size argument, return a square matrix with
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−## the dimension specified.  When called with more than one scalar argument the
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−## first two arguments are taken as the number of rows and columns and any
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−## further arguments specify additional matrix dimensions.  The size may also
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−## be specified with a vector of dimensions @var{sz}.
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−## @end deftypefn
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−
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−## Author: KH <Kurt.Hornik@wu-wien.ac.at>
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−## Description: Random deviates from the logistic distribution
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−
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−function rnd = logistic_rnd (varargin)
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−
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−  if (nargin < 1)
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−    print_usage ();
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−  endif
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−
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−  if (nargin == 1)
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−    if (isscalar (varargin{1}) && varargin{1} >= 0)
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−      sz = [varargin{1}, varargin{1}];
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−    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
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−      sz = varargin{1};
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−    else
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−      error ("logistic_rnd: dimension vector must be row vector of non-negative integers");
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−    endif
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−  elseif (nargin > 1)
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−    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
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−      error ("logistic_rnd: dimensions must be non-negative integers");
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−    endif
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−    sz = [varargin{:}];
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−  endif
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−
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−  rnd = - log (1 ./ rand (sz) - 1);
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−
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−endfunction
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−
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−
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−%!assert (size (logistic_rnd (3)), [3, 3])
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−%!assert (size (logistic_rnd ([4 1])), [4, 1])
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−%!assert (size (logistic_rnd (4,1)), [4, 1])
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−
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−%% Test input validation
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−%!error logistic_rnd ()
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−%!error logistic_rnd (-1)
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−%!error logistic_rnd (ones (2))
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−%!error logistic_rnd ([2 -1 2])
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−%!error logistic_rnd (1, ones (2))
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−%!error logistic_rnd (1, -1)
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−