
Risch Algorithm for Symbolic Integration - ColinWright
https://en.wikipedia.org/wiki/Risch_algorithm
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ynfnehf
I recently read about Rubi, which instead uses a huge decision tree and
pattern matching to do symbolic integration. Kind of like how humans do it.
There are a lot of interesting thoughts on their website, I would highly
recommend checking it out. Skimming through the pdfs of rules was a lot of
fun.

[https://rulebasedintegration.org/](https://rulebasedintegration.org/)

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sanxiyn
SymPy implements this algorithm, start here:
[https://github.com/sympy/sympy/blob/master/sympy/integrals/r...](https://github.com/sympy/sympy/blob/master/sympy/integrals/risch.py)

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nimish
Not all of it, notably the algebraic extensions which are quite difficult to
grasp.

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slavik81
The Risch Algorithm was mentioned in a recent XKCD[1]. Perhaps that was the
trigger for this submission.

There were a few rabbit holes to investigate from that comic. Bessel functions
were what first piqued my curiosity. I never did get around to the Wikipedia
page, but Wikiquote[2] had some interesting quips.

[1]: [https://xkcd.com/2117/](https://xkcd.com/2117/) [2]:
[https://en.wikiquote.org/wiki/Bessel_function](https://en.wikiquote.org/wiki/Bessel_function)

