Mercurial > hg > octave-lyh
annotate scripts/statistics/distributions/discrete_pdf.m @ 11094:add5beb3b845
avoid use of | and & in IF conditions in statistics distribution functions
| author | John W. Eaton <jwe@octave.org> |
|---|---|
| date | Sat, 09 Oct 2010 11:55:51 -0400 |
| parents | 1c6ff93c025a |
| children | 83da69c6e7be |
| rev | line source |
|---|---|
| 7017 | 1 ## Copyright (C) 1996, 1997, 1998, 2000, 2002, 2004, 2005, 2006, 2007 |
| 2 ## Kurt Hornik | |
| 3426 | 3 ## |
| 3922 | 4 ## This file is part of Octave. |
| 5 ## | |
| 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 | |
| 7016 | 8 ## the Free Software Foundation; either version 3 of the License, or (at |
| 9 ## your option) any later version. | |
| 3426 | 10 ## |
| 3922 | 11 ## Octave is distributed in the hope that it will be useful, but |
| 3191 | 12 ## WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 3426 | 14 ## General Public License for more details. |
| 15 ## | |
| 3191 | 16 ## You should have received a copy of the GNU General Public License |
| 7016 | 17 ## along with Octave; see the file COPYING. If not, see |
| 18 ## <http://www.gnu.org/licenses/>. | |
| 3191 | 19 |
| 3456 | 20 ## -*- texinfo -*- |
| 21 ## @deftypefn {Function File} {} discrete_pdf (@var{x}, @var{v}, @var{p}) | |
| 22 ## For each element of @var{x}, compute the probability density function | |
| 6754 | 23 ## (PDF) at @var{x} of a univariate discrete distribution which assumes |
| 3456 | 24 ## the values in @var{v} with probabilities @var{p}. |
| 25 ## @end deftypefn | |
| 3191 | 26 |
| 5428 | 27 ## Author: KH <Kurt.Hornik@wu-wien.ac.at> |
| 3456 | 28 ## Description: pDF of a discrete distribution |
| 3191 | 29 |
| 3456 | 30 function pdf = discrete_pdf (x, v, p) |
| 3426 | 31 |
| 3191 | 32 if (nargin != 3) |
| 6046 | 33 print_usage (); |
| 3191 | 34 endif |
| 35 | |
| 4859 | 36 sz = size (x); |
| 3191 | 37 |
| 4030 | 38 if (! isvector (v)) |
| 3456 | 39 error ("discrete_pdf: v must be a vector"); |
| 4030 | 40 elseif (! isvector (p) || (length (p) != length (v))) |
| 3456 | 41 error ("discrete_pdf: p must be a vector with length (v) elements"); |
| 42 elseif (! (all (p >= 0) && any (p))) | |
| 43 error ("discrete_pdf: p must be a nonzero, nonnegative vector"); | |
| 3191 | 44 endif |
| 45 | |
| 4859 | 46 n = numel (x); |
| 3456 | 47 m = length (v); |
| 48 x = reshape (x, n, 1); | |
| 49 v = reshape (v, 1, m); | |
| 50 p = reshape (p / sum (p), m, 1); | |
| 3191 | 51 |
|
10524
1c6ff93c025a
Reimplement the other discrete distribution functions using lookup
David Bateman <dbateman@free.fr>
parents:
7017
diff
changeset
|
52 pdf = NaN (sz); |
| 3456 | 53 k = find (!isnan (x)); |
| 54 if (any (k)) | |
| 3191 | 55 n = length (k); |
|
10524
1c6ff93c025a
Reimplement the other discrete distribution functions using lookup
David Bateman <dbateman@free.fr>
parents:
7017
diff
changeset
|
56 pdf (k) = p (lookup (v, x(k), 'm')); |
| 3191 | 57 endif |
| 58 | |
| 59 endfunction |