TensorNetwork.find_order() returns None when cost/cw is high about acqdp

[cupjinhuang]

Hello ChienKaiMa,

Thank you very much for raising this issue. We will look into that and make corrections accordingly. In the meantime, could you provide a test script that reproduces this error? Thanks!

Cupjin

[ChienKaiMa]

I have difficulties attaching files right here, so I forked the repository and committed the modified code and circuit files in use in ChienKaiMa@fce402e

[cupjinhuang]

Hello @ChienKaiMa ,

I have added a warning when the order finding returns None. However I did not change the return type, since it being None is used elsewhere.

Regarding your concern that it took too long for the process to halt, I have also slightly changed the code logic for slight improvement of performance. I would like to mention that there are cases where it is not clear if the tensor network is indeed intractable or not without a heavy pre-processing. In cases where such pre-processing is not needed, I suggest changing the slicer.slicer_params.num_iter_before in khp_params.json to a smaller number. This should help accelerate the pre-processing process.

Hope this helps.

Cupjin