e3x.ops.indexed.dense_to_sparse_indices

e3x.ops.indexed.dense_to_sparse_indices(adj_idx, pad_idx=None)[source]

Converts a dense index list to a sparse index list.

Note: Not compatible with jax.jit or jax.vmap because boolean arrays are not concrete.

Parameters:

adj_idx (<class 'Integer[Array, '... N M']'>) – Adjcency indices.
pad_idx (Optional[int], default: None) – All indices >= pad_idx are assumed to be padding. If this is None, all indices are assumed to be non-padding entries.

Return type:

Tuple[Integer[Array, '... P'], Integer[Array, '... P']]

Returns:

The corresponding sparse index list returned as a tuple (dst_idx, src_idx) with destination and source indices, respectively.