Hi, We've run into some problems recently with our evolution code, which boil done to the fact that we'd developed the code to support the sort of reflection symmetry defined in cartgrid3d, but recently started working with other thorns which are expecting the use of ReflectionSymmetry to define reflection symmetries. I assume that the motivation for this transition was to support more general grids, multipatch codes, etc, but I haven't found any documentation for the ReflectionSymmetry thorn, or any explanation of its use. One likely problem we are having is that we haven't applied any tensor-related tags in our interface.ccl, and rumor has it around here that ReflectionSymmetry relies on these tags. Presumably there are other EinsteinToolkit thorns which rely on tensor tags as well. I did find one document giving some explanation of tensor tags
http://cactuscode.org/documentation/CoreDoc.pdf
(thanks Erik). Erik outlines a number of potential tags there, but I would like to know which of these are required to support interaction which the various thorns in the toolkit?
Looking at various other interface.ccl files, there didn't seem to be a high degree of consistency about which tags are set. Some also naively appear to be set incorrectly, in ML_BSSN. For instance:
CCTK_REAL ML_trace_curv type=GF timelevels=3 tags='tensortypealias="Scalar" tensorweight=1.0000000000000000000' { trK } "ML_trace_curv"
Which seems to declare the trK to be a tensor density. If this is indeed wrong, and no one has noticed, then I infer that tensorweight may not really be used by anything important.
If anyone can clarify these issues for me I would appreciate it. Thanks, John.