Type Alias IndexId 

pub type IndexId = usize;

A unique identifier for a tensor index.

Tensor indices are identified in two distinct locations by this type alias:

1. Local Tensor indices: TensorExpression objects generate tensor data in a specific order. The ordering of their local tensor indices is identified by their local index ids. These do not change unless the TensorExpression’s internal symbolic expression changes. Therefore, it is important to track it’s local tensor index ordering, so we can accurately perform contractions dictated by the network. See [TensorIndex] for more information.

2. Global Tensor Network indices: The entire network will have a list of indices and each will have its own id. See [NetworkIndex] for more information.