#2902: CarpetX: interpolation with z-reflection symmetry only works for Psi4

Reporter: Miren Radia Status: submitted Milestone: Version: development version Type: bug Priority: major Component: CarpetX

Currently the end of `CarpetX::interpolate` looks like this:

```c++ // Apply symmetries to interpolated values assert(!reflection_x); assert(!reflection_y); assert(!reflection_upper_x); assert(!reflection_upper_y); assert(!reflection_upper_z); if (reflection_z) { // The code below is only valid for Psi4 assert(nvars == 2); assert(varinds[0] == CCTK_VarIndex("Weyl::Psi4re")); assert(varinds[1] == CCTK_VarIndex("Weyl::Psi4im")); // l^a = et^a + er^a // n^a = et^a - er^a // m^a = etheta^a + i ephi^a // Psi4 = C_abcd m-bar^b n^b m-bar^c n^d for (int n = 0; n < npoints; ++n) { if (symmetry_reflected_z[n]) { resultptrs[0][n] = -resultptrs[0][n]; resultptrs[1][n] = +resultptrs[1][n]; } } } ```

([link to source](https://github.com/EinsteinToolkit/CarpetX/blob/2cba1e969badbe8e6a11bacd6ac8...)

These assertions are failed when you have z-reflection symmetry and try to interpolate different variables.

Note that has already been reported in [an issue in the CarpetX GitHub repo](https://github.com/EinsteinToolkit/CarpetX/issues/146) but I thought I’d open a ticket here given the lack of activity there.

-- Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/2902/carpetx-interpolat...