Software Listing of Author : "Bill Davidson"
- Call a waitbar from within a DLL written in C
- License: Freeware
- Price: 0.00


When a DLL takes a long time to run, things go silent. It can look like the program has crashed even when it is running along just fine. The Matlab waitbar() function can be used in Matlab, but a waitbar is not available in C. However, Matlab can be called from C, so the user can still be notified that processing is still taking place. This code is an example of how to call the waitbar() from within a DLL that is written in C.
- Publisher: Bill Davidson
- Date Released: 05-06-2013
- Download Size: 10 KB
- Download
- Platform: Matlab, Scripts
- candlesticks
- License: Shareware
- Price:


This is a little function that charts financial data using Japanese candlesticks. It takes as input highs, lows, opens, and closes, and plots the candlestick boxes, both the body part, black or white, and the shadow part, above and below the body part. It comes with a little test driver that you can delete. It is a small function. It works as-is but can be customized easily to fit your personal charting tastes, such as adding in volume data, changing colors, etc.
- Publisher: Bill Davidson
- Date Released: 14-04-2013
- Download Size: 10 KB
- Download
- Platform: Matlab, Scripts
- Hurst exponent
- License: Shareware
- Price:


This is an implementation of the Hurst exponent calculation that is smaller, simpler, and quicker than most others. It does a dispersional analysis on the data and then uses Matlab's polyfit to estimate the Hurst exponent. It comes with a test driver that you can delete.
- Publisher: Bill Davidson
- Date Released: 11-05-2013
- Download Size: 10 KB
- Download
- Platform: Matlab, Scripts
- Levi-Civita Symbol
- License: Shareware
- Price:


This is an implementation of the Levi-Civita symbol, also known as the permutation tensor, or "epsilon i j k". The function supports not just three but two, four, five etcetera indices. It is fairly fast. Most of the file is a test driver which can be deleted. To see how it works just type "levi_civita".
- Publisher: Bill Davidson
- Date Released: 06-04-2013
- Download Size: 10 KB
- Download
- Platform: Matlab, Scripts
- pop-up file viewer
- License: Shareware
- Price:


This is a little pop-up file viewer. It will display the human-readable ASCII portions of a file. It will also handle a Matlab MAT file by making use of the Matlab Diary and the disp() feature to format the file's contents. It can be embedded within another GUI application to provide a handy 'View File' capability.
- Publisher: Bill Davidson
- Date Released: 24-06-2013
- Download Size: 10 KB
- Download
- Platform: Matlab, Scripts
- Quaternion belt-trick
- License: Freeware
- Price: 0.00


This program demonstrates the quaternion belt-trick, also known as the Dirac belt-trick and the waiter trick. It generates an AVI movie file (also included) which shows a stereo movie of the belt-trick in action. Notes: (1) If you want to save time and see the end-result, just watch the included AVI movie. It opens in Windows Explorer with Windows Media Player. The program is really included just to show you how it was done. (2) The movie is stereoscopic. If you sit back at least a meter from the screen and cross your eyes slightly to fuse the two images in your "mind's eye", you should get a nice stereoscopic effect. (3) The program takes a few minutes to generate the AVI movie - about 10 minutes on a 3GHz machine. It produces one figure for each frame of video and takes a little software snapshot of each one. There are 96...
- Publisher: Bill Davidson
- Date Released: 23-06-2013
- Download Size: 3738 KB
- Download
- Platform: Matlab, Scripts
- Quaternion data class
- License: Shareware
- Price:


This is an implementation of quaternions based upon the Cayley-Dickson construction. It make use of recursion and inheritance of data classes. A base type called 'komplex' is defined that acts like MatLab's complex type but is inheritable. It is used to define the other data types recursively. The three normed division algebras, 'komplex', 'quaternion', and 'octonion', are supported in this way. I tossed in the sedenions, too, but of course they are not nicely-normed. The package includes the standard trig functions, log, exp, rotations, and handles symbolic expressions. If you install the package in your 'my_classes' subdirectory and use the pathtool to point to it, the package will be available to you if you get a hankering to perform any quaternion or octonion arithmetic. Also included is a test directory with a script called...
- Publisher: Bill Davidson
- Date Released: 06-05-2013
- Download Size: 51 KB
- Download
- Platform: Matlab, Scripts