From maintainers-request at octave dot org Tue Nov 30 21:54:58 2004
Subject: Re: full/sparse/banded/triangular matrices...
From: Paul Kienzle <pkienzle at users dot sourceforge dot net>
To: octave maintainers mailing list <maintainers at octave dot org>
Date: Tue, 30 Nov 2004 22:55:32 -0500

LAPACK also has tridiagonal functions.  In the spline code we are
doing a couple of rotations outside the solver so that the cyclic
case doesn't need a full matrix solve.  I doubt you want to support
a mostly banded matrix class though.

Another matrix attribute to consider is a transpose marker, but like
triangular matrices, this only gives a small speedup compared to the
cost of the op.

- Paul