Modernize test_sparse. (#17324)
Summary:
Our sparse tests still almost exclusively use legacy constructors. This means you can't, for example, easily test scalars (because the legacy constructors don't allow them), and not surprisingly, many operations are broken with sparse scalars.
Note: this doesn't address the SparseTensor constructor itself, because there is a separate incompatibility there that I will address in a follow-on commit, namely, that torch.sparse.FloatTensor() is supported, but torch.sparse_coo_tensor() is not (because the size is ambiguous).
The follow-on PR will explicitly set the size for sparse tensor constructors and add a test for the legacy behavior, so we don't lose it.
Included in this PR are changes to the constituent sparse tensor pieces (indices, values):
1) IndexTensor becomes index_tensor
2) ValueTensor becomes value_tensor if it is a data-based construction, else value_empty.
3) Small changes around using the legacy tensor type directly, e.g. torch.FloatTensor.dtype exists, but torch.tensor isn't a type.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/17324
Differential Revision: D14159270
Pulled By: gchanan
fbshipit-source-id: 71ee63e1ea6a4bc98f50be41d138c9c72f5ca651
