Mercurial > hg > octave-lyh
annotate scripts/sparse/spstats.m @ 7515:f3c00dc0912b
Eliminate the rest of the dispatched sparse functions
| author | David Bateman <dbateman@free.fr> |
|---|---|
| date | Fri, 22 Feb 2008 15:50:51 +0100 |
| parents | 3f29467c1667 |
| children | eb63fbe60fab |
| rev | line source |
|---|---|
| 7017 | 1 ## Copyright (C) 2004, 2005, 2006, 2007 Paul Kienzle |
| 5164 | 2 ## |
| 7016 | 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 | |
| 7 ## the Free Software Foundation; either version 3 of the License, or (at | |
| 8 ## your option) any later version. | |
| 9 ## | |
| 10 ## Octave is distributed in the hope that it will be useful, but | |
| 11 ## WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 ## General Public License for more details. | |
| 14 ## | |
| 15 ## You should have received a copy of the GNU General Public License | |
| 16 ## along with Octave; see the file COPYING. If not, see | |
| 17 ## <http://www.gnu.org/licenses/>. | |
| 5164 | 18 |
| 19 ## -*- texinfo -*- | |
| 6547 | 20 ## @deftypefn {Function File} {[@var{count}, @var{mean}, @var{var}] =} spstats (@var{s}) |
| 21 ## @deftypefnx {Function File} {[@var{count}, @var{mean}, @var{var}] =} spstats (@var{s}, @var{j}) | |
| 5164 | 22 ## Return the stats for the non-zero elements of the sparse matrix @var{s}. |
| 23 ## @var{count} is the number of non-zeros in each column, @var{mean} | |
| 24 ## is the mean of the non-zeros in each column, and @var{var} is the | |
| 25 ## variance of the non-zeros in each column. | |
| 26 ## | |
| 5584 | 27 ## Called with two input arguments, if @var{s} is the data and @var{j} |
| 5164 | 28 ## is the bin number for the data, compute the stats for each bin. In |
| 29 ## this case, bins can contain data values of zero, whereas with | |
| 30 ## @code{spstats (@var{s})} the zeros may disappear. | |
| 31 ## @end deftypefn | |
| 32 | |
| 6498 | 33 function [count, mean, var] = spstats (S, j) |
| 34 | |
| 35 if (nargin < 1 || nargin > 2) | |
| 6046 | 36 print_usage (); |
| 5164 | 37 endif |
| 38 | |
| 6498 | 39 if (nargin == 1) |
| 40 [i, j, v] = find (S); | |
| 5164 | 41 else |
| 42 v = S; | |
| 43 i = 1:length (v); | |
| 44 S = sparse (i, j, v); | |
| 45 endif | |
| 5584 | 46 [n, m] = size (S); |
| 5164 | 47 |
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7515
f3c00dc0912b
Eliminate the rest of the dispatched sparse functions
David Bateman <dbateman@free.fr>
parents:
7287
diff
changeset
|
48 count = sum (sparse (i, j, 1, n, m)); |
| 5164 | 49 if (nargout > 1) |
|
7515
f3c00dc0912b
Eliminate the rest of the dispatched sparse functions
David Bateman <dbateman@free.fr>
parents:
7287
diff
changeset
|
50 mean = sum (S) ./ count; |
| 7151 | 51 endif |
| 5164 | 52 if (nargout > 2) |
| 5775 | 53 ## FIXME Variance with count = 0 or 1? |
| 5164 | 54 diff = S - sparse (i, j, mean(j), n, m); |
|
7515
f3c00dc0912b
Eliminate the rest of the dispatched sparse functions
David Bateman <dbateman@free.fr>
parents:
7287
diff
changeset
|
55 var = sum (diff .* diff) ./ (count - 1); |
| 7151 | 56 endif |
| 57 | |
| 5164 | 58 endfunction |
| 59 | |
| 60 %!test | |
| 61 %! [n,m,v] = spstats([1 2 1 2 3 4],[2 2 1 1 1 1]); | |
| 7287 | 62 %! assert(n,sparse([4,2])); |
| 63 %! assert(m,sparse([10/4,3/2]),10*eps); | |
| 64 %! assert(v,sparse([5/3,1/2]),10*eps); |