# qml.utils¶

Warning

Unless you are a PennyLane or plugin developer, you likely do not need to use these utility functions.

This module contains utilities and auxiliary functions which are shared across the PennyLane submodules.

## Functions¶

 decompose_hamiltonian(H[, hide_identity]) Decomposes a Hermitian matrix into a linear combination of Pauli operators. expand(matrix, original_wires, expanded_wires) Expand a an operator matrix to more wires. expand_vector(vector, original_wires, …) Expand a vector to more wires. Eigenvalues for $$A^{\otimes n}$$, where $$A$$ is Pauli operator, or shares its eigenvalues. sparse_hamiltonian(H[, wires]) Computes the sparse matrix representation a Hamiltonian in the computational basis. unflatten(flat, model) Wrapper for _unflatten().