Potential bugs in the GTS.py

[VAN-QIAN]

Dear Libcity team, Greetings!

1. When I tried GTS, I got an error info as follows: RuntimeError: sparse_.is_sparse() INTERNAL ASSERT FAILED on torch

After checking the code, I found that this error may be caused by some sparse operations,like torch.sparse.mm in the line 97 and 102 of GTS.py.

Now everything goes well after I removed the sparse in these two lines,i.e., they are just torch.mm now.

2. By the way, I found that there is a function called _build_sparse_matrix(), but it hasn't been used in the GTS.py

Will these be potential bugs in the GTS.py?

[aptx1231]

Yes, you are right, we will fix these problems recently