make Extract work with Carpet

This pull request contains three patches needed for Extract to be usable with Carpet in AMR simulations. Admittedly, these are workarounds and Exact would probably need to be redesigned to more transparently work with AMR grids. I have tested these changes and I can now use Extract to Extract gravitational wave and.the results are consistent with those of Multipole + integration of Psi4.

‌

Extract: do not check grid extension

Extract is not producing any output, because it incorrectly assumes that the detectors are outside of the grid. This patch is a workaround which removes this check.
Extract: set variables prolongation to None
Extract: only extract waves in one refinement level

Extract was previously attempting to extract waves on all refinement levels, producing incorrect output for those levels that do not include the extraction surfaces. This patch adds a parameter to Extract to specify which refinement level to analyize.

In the long term, it would be cleaner to redesign Extract to work in GLOBAL mode, rather than in LOCAL mode.

‌

Comments (3)