If one attempts to perform an interpolation to a single point in 3D before the transposes are created, Dedalus will hang if one of the bases is Chebyshev.
A workaround is to force the transposes to be created before the interpolation, for example by doing
The attached script provides a minimal working example. It runs fine in serial, but hangs in parallel if the workaround remains commented out.
- the bug does not manifest if interpolation is done along only one dimension (even if it is the Chebyshev dimension)
- This problem occurs in practice if one wishes to drop a "probe" in the flow to get a field at a given point and output it to a high time-cadence analysis task. The simulation will hang if the analysis task is triggered before the first timestep (as it is by default)