1 ## Copyright (C) 2012 Rik Wehbring
2 ## Copyright (C) 1995-2012 Kurt Hornik
4 ## This file is part of Octave.
6 ## Octave is free software; you can redistribute it and/or modify it
7 ## under the terms of the GNU General Public License as published by
8 ## the Free Software Foundation; either version 3 of the License, or (at
9 ## your option) any later version.
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12 ## WITHOUT ANY WARRANTY; without even the implied warranty of
13 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 ## General Public License for more details.
16 ## You should have received a copy of the GNU General Public License
17 ## along with Octave; see the file COPYING. If not, see
18 ## <http://www.gnu.org/licenses/>.
21 ## @deftypefn {Function File} {} geornd (@var{p})
22 ## @deftypefnx {Function File} {} geornd (@var{p}, @var{r})
23 ## @deftypefnx {Function File} {} geornd (@var{p}, @var{r}, @var{c}, @dots{})
24 ## @deftypefnx {Function File} {} geornd (@var{p}, [@var{sz}])
25 ## Return a matrix of random samples from the geometric distribution with
28 ## When called with a single size argument, return a square matrix with
29 ## the dimension specified. When called with more than one scalar argument the
30 ## first two arguments are taken as the number of rows and columns and any
31 ## further arguments specify additional matrix dimensions. The size may also
32 ## be specified with a vector of dimensions @var{sz}.
34 ## If no size arguments are given then the result matrix is the size of
38 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
39 ## Description: Random deviates from the geometric distribution
41 function rnd = geornd (p, varargin)
50 if (isscalar (varargin{1}) && varargin{1} >= 0)
51 sz = [varargin{1}, varargin{1}];
52 elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
55 error ("geornd: dimension vector must be row vector of non-negative integers");
58 if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
59 error ("geornd: dimensions must be non-negative integers");
64 if (!isscalar (p) && !isequal (size (p), sz))
65 error ("geornd: P must be scalar or of size SZ");
69 error ("geornd: P must not be complex");
72 if (isa (p, "single"))
80 rnd = floor (- rande (sz) ./ log (1 - p));
84 rnd = zeros (sz, cls);
85 elseif (p < 0 || p > 1)
89 rnd = floor (- rande (sz) ./ log (1 - p));
91 k = !(p >= 0) | !(p <= 1);
101 %!assert(size (geornd (0.5)), [1, 1]);
102 %!assert(size (geornd (0.5*ones(2,1))), [2, 1]);
103 %!assert(size (geornd (0.5*ones(2,2))), [2, 2]);
104 %!assert(size (geornd (0.5, 3)), [3, 3]);
105 %!assert(size (geornd (0.5, [4 1])), [4, 1]);
106 %!assert(size (geornd (0.5, 4, 1)), [4, 1]);
108 %% Test class of input preserved
109 %!assert(class (geornd (0.5)), "double");
110 %!assert(class (geornd (single(0.5))), "single");
111 %!assert(class (geornd (single([0.5 0.5]))), "single");
112 %!assert(class (geornd (single(0))), "single");
113 %!assert(class (geornd (single(1))), "single");
115 %% Test input validation
117 %!error geornd (ones(3),ones(2))
118 %!error geornd (ones(2),ones(3))
120 %!error geornd (1, -1)
121 %!error geornd (1, ones(2))
122 %!error geornd (1, [2 -1 2])
123 %!error geornd (ones(2,2), 2, 3)
124 %!error geornd (ones(2,2), 3, 2)