[Jprogramming] Geometric algebra

[Arnab Chakraborty]

Thank you all so much for all your excellent suggestions. In fact, Bo's
idea was what I started with. But two things (not mentioned in my original
mail) prevented me from using that approach. First, my vector space has 32
dimensions, and most of my vectors will be sparse. Second, I have a
somewhat complicated multiplication rule for the basis vectors which
requires manipulation of the indices (basically taking symmetric difference
of the two index sets).



On Tue, 26 Nov 2019, 10:20 Don Kelly, <dhky at shaw.ca> wrote:

> you can also look at the base vectors using complex numbers
>
> +. +/ 2.3 0j3.9 3.1
>
> 5.4 3.9
>
>
> Don Kelly
>
>
> On 2019-11-25 1:39 p.m., 'Bo Jacoby' via Programming wrote:
> >   Enumerate your base vectors 1 0 and 0 1 etc.
> >
> >     (2.3*1 0)+(3.9*0 1)+(3.1*1 0)
> >
> > 5.4 3.9
> >
> >
> >
> > Thanks.
> > Bo.    Den mandag den 25. november 2019 19.45.04 CET skrev Raul Miller <
> rauldmiller at gmail.com>:
> >
> >   Or, slightly more efficient (if that matters):
> >
> >    V1=: |:(2 3 4;2.3),(1 2;3.9),: 2 3 4;3.1
> >    V2=: (~.@{.,:+/&.:>/./)V1
> >    V2-:|:(2 3 4;5.4),: 1 2;3.9
> >
> > (Caution: email clients have become hostile to copy&paste, and may not
> > represent code accurately.)
> >
> > Thanks,
> >
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