[Users] Output file for one specific grid point

[Haas, Roland]

Hello Severin,

> However if I want to choose a point inside the spherical part
> (outside of the cartesian grid) I can not gather any data.
> 
> I assume that the output thorn is only aware of the cartesian
> coordinates? Do you (or anyone else) know if there is a way to bypass
> this issue?
The output thorn is CarpetIOASCII, though I am not familiar enough with
it to know exactly how it finds out which point to output. It may well
not be aware of Llama (it would then use the "local" coordinates
instead of the "global", Cartesian ones).

You could write some C code to use Cactus's interpolator to get
interpolate the data. If the coordinate given is the location of an
actual grid point then there is (effectively) no interpolation. For an
example on how to use it, please see the Cactus docs:

https://www.einsteintoolkit.org/referencemanual/ReferenceManualch2.html#x4-110000A2

You could (ab)use CactusNumerical's InterpToArray thorn which lets you
do the same without writing code. For an example use, please see its
tests though for your use you will want to use the "scalar_vars" etc
parameters instead of "array1d_vars".

Yours,
Roland

-- 
My email is as private as my paper mail. I therefore support encrypting
and signing email messages. Get my PGP key from http://pgp.mit.edu .
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 833 bytes
Desc: OpenPGP digital signature
Url : http://lists.einsteintoolkit.org/pipermail/users/attachments/20191015/cd0ab483/attachment.bin