TechBlog

Descartes

This is a Windows application for drawing graphs of mathematical functions. See screenshots below for an idea of what it can do. You do not choose from a limited set of offered functions - an expression evaluator can deal with an extremely wide range of expressions from simple polynomials, trigonometric, hyperbolic, exponential terms, differentials and integrals, and sums and products of series.

Requirements : it works on Windows XP. I think it would work back to Windows 98. Let me know.

Since its release in April 2006 Descartes had over 4800 downloads from this site.

Versions

Current release is version 1.2. New features in this release are:

File.. New and File..Save
Memo - this is some text saved with a file, giving an explanation or notes about the idea behind the file contents. The memo is displayed when the file loads, and can be reviewed/edited from the menu Memo option.
Files remember the ‘context’ of what was saved eg polar or parametric functions, and the appropriate dialog box is displayed when the file opens.
Mouse right-click on the graph background offers various options, some of which are obvious - zoom in and out, centre, and reset graph limits to the original : +/- 5. The non-obvious options will display a chord on a function, showing the ‘rise and run’, and the slope of the chord as ‘rise over run’. With appropriate zoom in, continuous functions become locally straight, and the chord slope becomes the function differential coefficient. The other options enable the user to select where (what x value) the chord is shown at, or to use the next function, if several functions are being displayed.

Two implicit relations can be displayed. This is to enable simultaneous equations to be written in conventional form.

If a mouse wheel is available, it does zoom in and out.

Some ‘example’ files are supplied to show what can be done.

Download and install

Download this file (152 kB as a zipped file).

Unzip it into a suitable directory - c:/descartes or wherever you like. Then create a shortcut on your desktop to descartes.exe. Drag a copy to the Start menu if you like. Simple. Descartes does not alter the system registry, install or change any dlls, or anything else which would alter the operating system.

Here is the Website for this Product

http://www.waltermilner.com/descartes/descartes.htm