From 6fe8b248bf94f778b20ddcc331f54c5394118d97 Mon Sep 17 00:00:00 2001 From: jthorn Date: Wed, 15 Jun 2005 09:50:17 +0000 Subject: note problems with grid points at the origin git-svn-id: http://svn.einsteintoolkit.org/cactus/EinsteinInitialData/IDAxiBrillBH/trunk@78 0a4070d5-58f5-498f-b6c0-2693e757fa0f --- doc/TODO | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/doc/TODO b/doc/TODO index a339e11..948a31e 100644 --- a/doc/TODO +++ b/doc/TODO @@ -13,3 +13,16 @@ Part of this same change might also be to store the 2D elliptic results in Cactus grid arrays rather than native Fortran 90 arrays. This would let us use standard Cactus I/O methods to output the 2D elliptic results instead of the hard-wired code we use right now. + + + +For each Cactus grid point, IDAxiBrillBH calculates + eta := |log(2r/m)| +and uses this to interpolate into an internal grid. This internal grid +covers the range eta = 0 to etamax, where etamax defaults to 5.0. +So... for m=1, r must lie in the range 0.00337 to 74.2, or else the +computed eta value will fall outside the internal grid. + +It would be nice if this restriction could be lifted (eg allowing +a grid point at the origin). Maybe some sort of interpolation in real +space (instead of in eta-space) to fill in the hole at the origin? -- cgit v1.2.3