Downloading Descartes 4.0 from the developer's website was possible when we last checked. We cannot confirm if there is a free download of this software available. The software belongs to Education Tools. This program is a product of Walter Milner. The common filename for the program's installer is Descartes3.exe. We recommend checking the downloaded files with any free antivirus. The most popular versions among the software users are 4.0, 3.0 and 1.2.
From the developer:
Displays graphs of algebraic functions in a variety of forms. These include polar and cartesian co-ordinates, parametric and intrinsic functions. A wide range of functions are built-in, from simple trig and hyperbolic functions to things such as the ceil and gamma functions. On-screen HTML help is bulit-in.
You may want to check out more software, such as gitoolbox, roboBASIC or Mathematics Worksheet Factory, which might be similar to Descartes.