[Bug]: HostAPI empty sort throws an exception

[Robadob]

Bug Description

Carlos has found that if the below code is called when there are no agents, a CUDA invalid configuration exception will be raised.

To Reproduce

cell_agent = FLAMEGPU.agent("CELL") # agent list must be empty
cell_agent.sortInt("id", pyflamegpu.HostAgentAPI.Asc)

Raises

File "C:\Users\PC\anaconda3\envs\flamegpu_py310\lib\site-packages\pyflamegpu\pyflamegpu.py", line 14017, in sortInt
    return _pyflamegpu.HostAgentAPI_sortInt(self, *args)
pyflamegpu.pyflamegpu.FLAMEGPURuntimeException: (CUDAError) D:/a/FLAMEGPU2/FLAMEGPU2/include\flamegpu/simulation/detail/CUDAErrorChecking.cuh(28): CUDA Error: D:\a\FLAMEGPU2\FLAMEGPU2\src\flamegpu\simulation\detail\CUDAScatter.cu(218): cudaErrorInvalidConfiguration invalid configuration argument

Expected Behaviour

It should be a null-op, notice empty and skip the sort.

OS

No response

CUDA Versions

No response

GPUs

No response

GPU Driver

No response

Additional Information

No response

[cborau]

It would be useful to get either a meaningful error or just a warning (e.g. agent list is empty). It happened to me because all agents were dead and I hadn't noticed. It took a while to realize. Cheers

[Robadob]

I'm wary of adding an error, there are reasonable cases where a user may wish to always sort and the population sometimes be empty. The user shouldn't be required to do if(!empty) in my opinion.

Could add a warning on first occurence, bit ugly but probably harmless if left to seatbelts.

[mondus]

After discussion. It is proposed that the expected result should be a no op with no warning or error.