Struct Tensor 

pub struct Tensor {
    pub data: ArrayD<Complex64>,
    pub rank: usize,
    pub dimensions: Vec<usize>,
}

A tensor representing a quantum state or operation

Fields

data: ArrayD<Complex64>

The tensor data

rank: usize

The tensor rank (number of indices)

dimensions: Vec<usize>

The dimensions of each index

Implementations

impl Tensor

pub fn new(data: ArrayD<Complex64>) -> Self

Create a new tensor from a multi-dimensional array

pub fn from_matrix(matrix: &[Complex64], dim: usize) -> Self

Create a tensor from a matrix (gate)

pub fn qubit_zero() -> Self

Create a tensor representing the |0⟩ state

pub fn qubit_one() -> Self

Create a tensor representing the |1⟩ state

pub fn qubit_plus() -> Self

Create a tensor representing the |+⟩ state

pub fn contract( &self, other: &Self, self_axis: usize, other_axis: usize, ) -> QuantRS2Result<Self>

Contract this tensor with another tensor along specified axes.

Performs the Einstein summation over one pair of indices: result[i₀,…,iₙ₋₁, j₀,…,jₘ₋₁] = Σₖ self[…k…] * other[…k…] where k runs over self.dimensions[self_axis] (= other.dimensions[other_axis]).

The output shape is self.dimensions with self_axis removed, followed by other.dimensions with other_axis removed.

pub fn svd( &self, left_axes: &[usize], right_axes: &[usize], max_bond_dim: usize, ) -> QuantRS2Result<(Self, Self)>

Perform SVD decomposition on this tensor, splitting it into two lower-rank tensors.

The tensor is logically reshaped into a matrix by grouping left_axes into rows and right_axes into columns. The SVD is then computed and the result is split into two tensors:

• left_tensor: shape (*left_dims, bond_dim) — absorbs U * diag(S)
• right_tensor: shape (bond_dim, *right_dims) — contains Vᴴ

max_bond_dim caps how many singular values are kept (bond dimension).

Trait Implementations

impl Clone for Tensor

fn clone(&self) -> Tensor

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Tensor

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

Formats the value using the given formatter.