Yep, by using two different bases, one Chebyshev and one ultraspherical
(Gegenbauer) polynomials, differential operators become banded operators, and
can be solved in O(n) time.
On 19 Sep 2014, at 12:14 pm, DumpsterDoofus <[email protected]> wrote:
> Haha, I remember reading through your paper "A fast and well-conditioned
> spectral method" last year and feeling like my head was spinning afterwards.
> I vaguely recall that it views differential equations in GegenbauerC space, a
> basis choice which has a bunch of super convenient properties, all of which I
> have completely forgotten by now.