Windisc for Windows 95/98/ME/2K/XP/Vista (370K) (21 Mar 2008)
Click the above link to download the program.
Windisc is a collection of subprograms that deal with discrete-math topics such as apportionment, voting power, voting methods, and network analysis (traveling salesman problem, map-coloring, etc).
If the program behaves strangely, there is a page of FAQ, which may help. If not, you can e-mail me at the address found in the program’s Help|About dialog box.
Follow the links for more information about the Windows 95/98/ME/2K/XP/Vista version or the Windows 3.1 version.
Those who want to use the program to view graph files (g6 format) or squared rectangles should download this collection of supplementary examples (29 Jul 2007) and unzip it to the same directory where the program itself is kept.
21 Mar 2008: Fixed the circulant-graph code, which was producing sporadic nonsense.
8 Mar 2008: Added a new MST algorithm. Requesting a minimal-weight spanning tree for a graph that has no edges is interpreted as a request to use Euclidean distances as weights.
29 Jul 2007: Modified the squared-rectangle viewer so that it reads a newly produced compendium of 17th-order examples. If you like this topic and want to know more, you should visit Stuart Anderson’s site, which is where I obtain my data.
16 Jul 2007: Discovered a small bug that had been keeping the Graph window from reading Bouwkamp code for a “four-corner” squared rectangle, such as (102,85)(17,24,44)(79,23,10,7)(3,16,12)(13)(4,8)(56)(52). Should be ok now.
25 Jan 2007: The apportionment window is now equipped with a new mechanism for studying the effects of changing the divisor, and the priority listing is valid for all divisor methods.
4 Dec 2006: Fixed a small bug in the Banzhaf window. Conflicts involving the first named voting bloc were being misreported.
19 Nov 2006: Discovered how to word-wrap my help texts. I await news of unintended consequences.
1 Nov 2006: Graph windows are now equipped with an implementation of Brélaz’s DSATUR vertex-coloring algorithm. Please report any bugs.
21 Aug 2006: Graph windows can now be used to view “squared rectangles” and the associated electrical-circuit graphs. See the File help text for details. There are now several associated files in this package, which should be put in the same directory as the program itself. Please report any bugs.
1 Jul 2006: Installed a toolbar in Graph windows, and text insertions can now be tied to vertices.
25 Mar 2006: Graph windows can now be used to view graph6 files (a few examples of which are included in the zipfile), and the program has been taught to draw trees as planar graphs (without crossings).
16 Mar 2006: The program has been taught how to read and write graphs using the graph6 and digraph6 formats. It will also produce Schlegel diagrams for polyhedral graphs.
26 Feb 2006: The program now knows how to refine solutions to the TSP by switching pairs of edges.
10 Feb 2006: The program was not rejecting requests to apply the sorted-edges TSP algorithm to an incomplete graph. Now it is.
26 Jan 2006: Installed an Undo button in the Voting dialog.
19 Jan 2006: Apportionment files were not being displayed correctly after being opened. They should be ok now.
30 Dec 2005: A user reported that the Graph window was not keeping track of deleted vertices in the Misc|Data display. Should be ok now.
28 Dec 2005: In response to users reporting difficulty opening files by double-clicking file icons, new versions have been prepared that deal with file-naming conventions that allow spaces (and extra periods). See the FAQ.
17 Sept 2005: When the number of states in an Apportionment window was reduced (by choosing an early Census, for example), the program sometimes left a stray row or two at the bottom of the display. That should not happen any more.
19 Mar 2005: In the graph window, a few more entries added to the File|New menu. Also removed some stray characters from the slow-motion display for Dijkstra’s algorithm.
14 Mar 2005: In the graph window, the clipboard graphics routines have been improved — users who paste diagrams into their MS Word documents will be happy to see the improvement when printing. There are two new entries in the File|New menu. Also fixed a couple of minor bugs.
20 Feb 2005: The program was incorrectly applying the .ban extension to a Banzhaf power file, instead of the intended .bnz. I also fixed a couple of bugs in the Traveling-Salesman module, which was not remembering the “best solution so far”.
17 Feb 2005: Supplementary text inserted into a graph can now be rotated.
31 Jan 2005: Minor corrections: The text windows (help files, notebooks, tables, etc) were losing their carets (the blinking thing) now and then, and were not opening files correctly.
15 Jan 2005: It seems that the old “search” function that I installed years ago in text windows no longer works under Windows XP, so I had to revise it.
3 Jan 2005: In the Apportionment window, the District of Columbia had been given only two votes in the Electoral College calculations. That has now been fixed.
29 Jun 2004: The sorted-edges algorithm for the TSP was freezing the computer. Should be ok now.
28 Jun 2004: In the apportionment window, the Huntington-Hill algorithm was using a mistyped formula (and has been for a few weeks now!). Should be ok now.
27 Apr 2004: The Prim MST algorithm in the graph module was crashing. Should be ok now.
25 Apr 2004: The coloring algorithm in the graph module was making mistakes. Should be ok now.
9 Mar 2004: I revised the importing of text descriptions of graphs, so that users of the old 3.1 version can transfer their files (the dots, lines, weights, and arrows, anyway) via the clipboard. I also had to provide the missing “text out” function for the old 3.1 version.
3 Mar 2004: At long last, finished a new version of Windisc. I await suggestions and reports of bugs.
