1%SJGET_EXAMPLE a demo for SJget.
2%   This example script gets the index file of the SJSU Singular matrix collection,
3%   and then loads in all symmetric non-binary matrices, in increasing order of
4%   number of rows in the matrix.
5%
6%   Example:
7%       type SJget_example ; % to see an example of how to use SJget
8%
9%   See also SJget, SJweb, SJgrep.
10
11%   Derived from the ssget toolbox on March 18, 2008.
12%   Copyright 2007, Tim Davis, University of Florida.
13
14%   modified by L. Foster 09/17/2008
15
16type SJget_example ;
17
18index = SJget ;
19% find all symmetric matrices that are not binary,
20% have at least 4000 column and have a gap in the singular
21% values at the numerical rank of at least 1000
22f = find (index.numerical_symmetry == 1 & ~index.isBinary & ...
23    index.ncols >= 4000 & index.gap >= 1000 );
24% sort by the dimension of the numerical null space
25[y, j] = sort (index.ncols (f) - index.numrank (f) ) ;
26f = f (j) ;
27
28for i = f
29    fprintf ('Loading %s%s%s, please wait ...\n', ...
30	index.Group {i}, filesep, index.Name {i}) ;
31    Problem = SJget (i,index) ;
32    %display the problem structure
33    disp (Problem) ;
34    % display a plot of the singular values
35    SJplot(Problem) ;
36    shg
37    disp(' ')
38    disp(['dim. of numerical null space = ', ...
39        num2str(index.ncols (i) - index.numrank (i))]);
40    disp(' ')
41    pause(1)
42    %display the web page with matrix details
43    SJweb (i) ;
44    pause(1)
45end
46
47