Enum CanonicalForm 

#[repr(i32)]
pub enum CanonicalForm {
    Unitary = 0,
    LU = 1,
    CI = 2,
}

Canonical form for tensor train / tree tensor network.

Specifies the mathematical form of the canonical representation. Each form uses a specific factorization algorithm internally.

C API Representation

• T4A_CANONICAL_UNITARY = 0
• T4A_CANONICAL_LU = 1
• T4A_CANONICAL_CI = 2

Variants

Unitary = 0

Unitary (orthogonal/isometric) canonical form.

Each tensor is isometric towards the orthogonality center. Uses QR decomposition internally. Properties:

• Numerically stable
• Easy norm computation
• Standard canonical form for DMRG

LU = 1

LU-based canonical form.

Uses rank-revealing LU decomposition. Properties:

• Faster than QR
• One factor has unit diagonal

CI = 2

Cross Interpolation (CI) canonical form.

Uses CI/skeleton decomposition. Properties:

• Adaptive rank selection
• Efficient for low-rank structures

Implementations

impl CanonicalForm

pub fn from_i32(value: i32) -> Option<CanonicalForm>

Create from C API integer representation.

Returns None for invalid values.

pub fn to_i32(self) -> i32

Convert to C API integer representation.

pub fn name(&self) -> &'static str

Get form name as string.

Trait Implementations

impl Clone for CanonicalForm

fn clone(&self) -> CanonicalForm

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for CanonicalForm

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for CanonicalForm

fn default() -> CanonicalForm

Returns the “default value” for a type.

impl Hash for CanonicalForm

fn hash<__H>(&self, state: &mut __H)

where __H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for CanonicalForm

fn eq(&self, other: &CanonicalForm) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for CanonicalForm

impl Eq for CanonicalForm

impl StructuralPartialEq for CanonicalForm