Module operator 

Operator composition for Tree Tensor Networks.

This module provides traits and functions for working with operators on TreeTN states, including composing multiple non-overlapping operators into a single operator.

Key Types

• Operator: Trait for objects that can act as operators on tensor network states
• LinearOperator: MPO wrapper with index mapping for automatic transformations
• IndexMapping: Mapping between true site indices and internal MPO indices
• compose_exclusive_linear_operators: Compose non-overlapping LinearOperators into a single operator

Example

use tensor4all_core::{DynIndex, IndexLike};
use tensor4all_treetn::{apply_linear_operator, compose_exclusive_linear_operators, IndexMapping};

let mapping = IndexMapping {
    true_index: DynIndex::new_dyn(2),
    internal_index: DynIndex::new_dyn(2),
};

assert_eq!(mapping.true_index.dim(), mapping.internal_index.dim());
let _apply = apply_linear_operator::<tensor4all_core::TensorDynLen, usize>;
let _compose = compose_exclusive_linear_operators::<tensor4all_core::TensorDynLen, usize>;

Structs

ApplyOptions

Options for apply_linear_operator.

ArcLinearOperator

LinearOperator with Arc-based Copy-on-Write semantics.

IndexMapping

Mapping between true site indices and internal MPO indices.

LinearOperator

LinearOperator: Wraps an MPO with index mapping for automatic transformations.

Traits

Operator

Trait for operators that can act on tensor network states.

Functions

apply_linear_operator

Apply a LinearOperator to a TreeTN state: compute A|x⟩.

are_exclusive_operators

Check if a set of operators are exclusive (non-overlapping) on the target network.

build_identity_operator_tensor

Build an identity operator tensor for a gap node.

compose_exclusive_linear_operators

Compose exclusive LinearOperators into a single LinearOperator.