

Inverse symbolic calculator - Panoramix
http://ddrive.cs.dal.ca/~isc/index.html

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pg
Robert Morris wrote one of these in college in the mid 80s to help him do his
math homework.

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cperciva
The ISC is rather more advanced than what Robert Morris wrote. Among other
techniques, it uses the recently developed PSLQ integer relation finding
algorithm to identify any root of a polynomial with degree <= 5 and reasonable
height, or linear combinations of Pi, log(2), log(3), square roots, et cetera.

Interestingly, the ISC's job is made easier by the fact that numbers which
come up in "real life" tend to have linear combinations of "similar" values.
For example, Pi behaves like a logarithm, so linear combinations of Pi and
(poly)logarithms tend to pop up, while Pi^2 tends to occur in combination with
the product of two logarithms. As a result, the ISC is optimized to pass sets
of "similar" inputs to the PSLQ algorithm, which makes finding relations much
faster without missing anything interesting.

