[Users] questions on CarpetIOASCII

[Erik Schnetter]

On Sun, Oct 9, 2011 at 7:39 PM, Luca Baiotti <baiotti at ile.osaka-u.ac.jp> wrote:
> Hello,
>
> I was looking into the param.ccl of CarpetIOASCII (hg version) and found
> some deprecated parameters:
>
> BOOLEAN out3D_ghosts "Output ghost zones (DEPRECATED)"
> {
> } "yes"
>
>
> BOOLEAN out3D_outer_ghosts "Output outer boundary zones (assuming that
> there are nghostzones boundary points (DEPRECATED)"
> {
> } "yes"
>
> In what sense are they deprecated? I don't do 3D ASCII output, but I
> think that setting the above parameters to "no" would be better (see
> also below).

These are deprecated because they do not calculate the number of ghost
zones correctly; they make some assumptions that hold in many cases,
but may either output ghost zones or not output real grid points in
some cases.

> Furthermore,
>
> BOOLEAN out1D_d "Do output along the diagonal" STEERABLE = ALWAYS
> {
> } "yes"
>
> should also default to no, I suggest.
>
>
> Finally, I would also make the default of:
>
> BOOLEAN output_ghost_points "Output ghost points"
> {
> } "yes"
>
> to "no". This would also make the script
> CarpetIOASCII/src/util/Carpet2ygraph.pl
> work again (see other message about Carpet2ygraph.pl in this mailing list).
> Except for debugging, is there any advantage in outputting ghost zones?

That is correct, one only wants to look at ghost zones for debugging.
Do you want to open a TRAC request, or suggest this again after the
release? Carpet is now certainly mature enough so that debugging
output does not need to be the default any more.

-erik

-- 
Erik Schnetter <schnetter at cct.lsu.edu>   http://www.cct.lsu.edu/~eschnett/