Cartan package for differential forms and Cartan-Kahler analysis in Maple

This is a Maple package that I wrote for doing computations for the Cartan-Kahler analysis of linear Pfaffian systems.  It can compute structure equations, absorb the torsion whenever possible (and compute unabsorbable torsion when it is not possible), compute Cartan characters and test for involutivity, and compute prolongations.  Cartan is based on (and includes) the Forms package for doing computations involving differential forms, which was written by Yunliang Yu of Duke University and maintained by him through Maple V, Release 4.  It was revised for Maple V, Release 5 by myself, and for Maple 6 and higher by myself and Tom Ivey.

This version is current as of July 2025 and should be compatible with Maple versions up to Maple 2025.  (Admittedly, testing on recent versions of Maple has been limited; please feel free to submit bug reports to the email above!)

Changes and improvements as of 7/30/25 include:

• The "L" command has been renamed to "LLL" to avoid a conflict with a Maple variable.
  
• The package has been updated to avoid errors that began appearing in Maple 2022 - BIG thanks to Tom Ivey for this update!
  
• The Maple help interface has been deprecated, so the help pages are no longer available within Maple.  Instead, the text of the help pages is included in the download folder in the file "Cartan_Manual".
  

• In Worksheet mode (the original Maple interface for old-dogs-who-don't-like-new-tricks like me!), the default wedge product command is "&^".
  
• In Document mode, the default wedge product command is "&w"; the original version had to be changed because the "^" character creates an exponent in Document mode.
  

• Cartan package for Worksheet mode
• Cartan package for Document mode