[GiNaC-list] About non commutative transformations in GiNaC

Vladimir V. Kisil kisilv at maths.leeds.ac.uk
Mon Jan 23 11:32:43 CET 2017

>>>>> On Mon, 23 Jan 2017 00:35:56 +0500, abpetrov <abpetrov at ufacom.ru> said:
    ABP> Below is simple example of program with program output.  How to
    ABP> change the class ncsymbol so that it was possible to apply
    ABP> rules like a*ap==ap*a+1?

    If you need just an implementation of the Heisenberg commutation
  relations you can use clifford class for this. GiNaC clifford class
  can handle both anti-commutators (proper Clifford algebras) and
  commutators. The attached example show this: "+1" at the end of
  definition of e tells to use commutators.

  Many years ago I derived a class lie_algebra from the class clifford,
  it was able to represent an arbitrary Lie algebra. At that time it was
  badly written (messing with some pointers) and it does not work with
  the current GiNaC (as I have discovered yesterday). Yet, that can be
  done properly. However, the speed for large commutators was not great,
  Singular is doing this much better.

  Best wishes,
Vladimir V. Kisil                 http://www.maths.leeds.ac.uk/~kisilv/
  Book:     Geometry of Mobius Transformations     http://goo.gl/EaG2Vu
  Software: Geometry of cycles          http://moebinv.sourceforge.net/

-------------- next part --------------
A non-text attachment was scrubbed...
Name: test-ga.cpp
Type: text/x-c
Size: 753 bytes
Desc: GiNaC test
URL: <http://www.cebix.net/pipermail/ginac-list/attachments/20170123/88227900/attachment.cpp>

More information about the GiNaC-list mailing list