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[porky11]

I'd like to experiment a bit with GA, but don't understand, how to use this lib. Is it even suited for every geometric algebra? Because only e1e2e3 are exported, but you may also want to create larger e.

[bld]

Thanks for the feedback. You're the first! It should work for any algebra. The file 'eg.lisp' has examples on how to define the algebras of 2D and 3D Euclidean (E2 and E3), 3D homogenous (H3), and 2D and 3D conformal (C2 and C3). The arguments of the DEFG macro are:

• Name of the algebra
• List of basis vectors
• Metric: NIL for Euclidean, a vector of the basis vector dot-products with themselves for an orthogonal algebra, or a 2D array of the basis vector dot products for a non-orthogonal algebra. See 'metric.lisp'.

[porky11]

I already liked this some time ago, but didn't get it, and then wasn't really interested in lisp anymore anyway.