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annotate scripts/statistics/distributions/discrete_pdf.m @ 11523:fd0a3ac60b0e
update copyright notices
| author | John W. Eaton <jwe@octave.org> |
|---|---|
| date | Fri, 14 Jan 2011 05:47:45 -0500 |
| parents | 1740012184f9 |
| children | 19b9f17d22af |
| rev | line source |
|---|---|
| 11523 | 1 ## Copyright (C) 1996-2011 Kurt Hornik |
| 3426 | 2 ## |
| 3922 | 3 ## This file is part of Octave. |
| 4 ## | |
| 5 ## Octave is free software; you can redistribute it and/or modify it | |
| 6 ## under the terms of the GNU General Public License as published by | |
| 7016 | 7 ## the Free Software Foundation; either version 3 of the License, or (at |
| 8 ## your option) any later version. | |
| 3426 | 9 ## |
| 3922 | 10 ## Octave is distributed in the hope that it will be useful, but |
| 3191 | 11 ## WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 3426 | 13 ## General Public License for more details. |
| 14 ## | |
| 3191 | 15 ## You should have received a copy of the GNU General Public License |
| 7016 | 16 ## along with Octave; see the file COPYING. If not, see |
| 17 ## <http://www.gnu.org/licenses/>. | |
| 3191 | 18 |
| 3456 | 19 ## -*- texinfo -*- |
| 20 ## @deftypefn {Function File} {} discrete_pdf (@var{x}, @var{v}, @var{p}) | |
| 21 ## For each element of @var{x}, compute the probability density function | |
| 6754 | 22 ## (PDF) at @var{x} of a univariate discrete distribution which assumes |
| 3456 | 23 ## the values in @var{v} with probabilities @var{p}. |
| 24 ## @end deftypefn | |
| 3191 | 25 |
| 5428 | 26 ## Author: KH <Kurt.Hornik@wu-wien.ac.at> |
| 3456 | 27 ## Description: pDF of a discrete distribution |
| 3191 | 28 |
| 3456 | 29 function pdf = discrete_pdf (x, v, p) |
| 3426 | 30 |
| 3191 | 31 if (nargin != 3) |
| 6046 | 32 print_usage (); |
| 3191 | 33 endif |
| 34 | |
| 4859 | 35 sz = size (x); |
| 3191 | 36 |
| 4030 | 37 if (! isvector (v)) |
|
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Use uppercase for variable names in error() strings to match Info documentation. Only m-files done.
Rik <octave@nomad.inbox5.com>
parents:
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changeset
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38 error ("discrete_pdf: V must be a vector"); |
| 4030 | 39 elseif (! isvector (p) || (length (p) != length (v))) |
|
11472
1740012184f9
Use uppercase for variable names in error() strings to match Info documentation. Only m-files done.
Rik <octave@nomad.inbox5.com>
parents:
11156
diff
changeset
|
40 error ("discrete_pdf: P must be a vector with length (V) elements"); |
| 3456 | 41 elseif (! (all (p >= 0) && any (p))) |
|
11472
1740012184f9
Use uppercase for variable names in error() strings to match Info documentation. Only m-files done.
Rik <octave@nomad.inbox5.com>
parents:
11156
diff
changeset
|
42 error ("discrete_pdf: P must be a nonzero, nonnegative vector"); |
| 3191 | 43 endif |
| 44 | |
| 4859 | 45 n = numel (x); |
| 3456 | 46 m = length (v); |
| 47 x = reshape (x, n, 1); | |
| 48 v = reshape (v, 1, m); | |
| 49 p = reshape (p / sum (p), m, 1); | |
| 3191 | 50 |
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Reimplement the other discrete distribution functions using lookup
David Bateman <dbateman@free.fr>
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51 pdf = NaN (sz); |
| 3456 | 52 k = find (!isnan (x)); |
| 53 if (any (k)) | |
| 3191 | 54 n = length (k); |
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Sort values in discrete_pdf before calling lookup
David Bateman <dbateman@free.fr>
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55 [vs, vi] = sort (v); |
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83da69c6e7be
Sort values in discrete_pdf before calling lookup
David Bateman <dbateman@free.fr>
parents:
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diff
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56 pdf (k) = p (vi(lookup (vs, x(k), 'm'))); |
| 3191 | 57 endif |
| 58 | |
| 59 endfunction |