Albert Rich posthumous release

Sadly, Albert Rich, the author of Rubi passed away on August 11, 2023. Albert had been highly active in developing another release of Rubi.

This release are the untouched files from Albert's computer which were rescued by David Stoutemyer and mailed to me on a memory stick.

We considered making a number of bug fixes to this release, however I feel it's best if we have a release of Albert's final version of Rubi before we start making changes to the code base.

Note: I previously used the release tag 4.17.2 which was incorrect, the final release from Albert was 4.17.3.

Version 4.16.1.0

Rubi Engine version 4.16.1 incorporates significant enhancements to rules for integrating expressions involving algebraic functions, logarithms, inverse trig functions, and inverse hyperbolic functions.

Version 4.16.0.5

Small fix on the Rubi interface. See #19

Version 4.16.0.4

• Improve loading time of the package. After the first loading of Rubi (takes up to one or more minutes), the complete package is now stored in a binary format that allows to load Rubi in under a second
• Remove global Int definitions before loading Rubi to avoid shadow warning message

Version 4.16.0.3

This release adapts some of the features of the Steps and Stats display to make the work correctly in older Mathematica version. It was tested in Mathematica 7.0.1 on OSX and Mathematica 8 on Windows.

Furthermore, this release includes a zip that contains the bare Mathematica package. This makes downloading of the large repository zip for Mathematica versions that don't support paclet files unnecessary.

Version 4.16.0.2

This release includes fixes in both the integration rules and the interface. The release was tested against the 70000+ test-integrals and works as expected. The package now automatically uses $LoadElementaryFunctionRules=True and $LoadShowSteps=True if not defined otherwise.

In addition, it is now possible to return steps and statistics for an integration instead of only printing them. This has advantages when someone wants to automatically collect information for further processing. To use this feature, please set the following option which is True per default:

Steps[Int[Sqrt[x^3], x], RubiPrintInformation -> False]

The Stats function takes the same option now.

Version 4.15.2.1

This release contains many changes that allow using Rubi as a complete Mathematica package that can be installed as Paclet. List of changes

• Automatic extraction of Rubi rules from Albert's source notebooks
• Reworking parts of the Step routine to allow for a more consistent formatting
• Implementation of new visualizations for Rubi integration steps and statistics
• Minor fixes in the integration rules

One major change for the user is that in order to see integration steps and statistics, the usage is now

Steps[Int[expr,x]]
Step[Int[expr,x]]
Stats[Int[expr,x]]

• Stats[Int[expr,var]] returns now a list {stats, antiderivative} so that you can use the statistics for inspection (instead of simply printing it).
• A minor issue with GtQ, an internal function, was fixed
• the output of Stats has now accessor for all fields:

{stats, int} = Stats[Int[expr, var]];
stats["Steps"]
stats["NumberOfRules"]
stats["InputLeafCount"]
stats["OutputLeafCount"]
stats["Ratio"]
stats["Rules"]