openfermion.utils.count_qubits

Compute the minimum number of qubits on which operator acts.

Main aliases

openfermion.utils.count_qubits(
    operator
)

Used in the tutorials
Circuits 2: Linear Trotter steps of diagonal Coulomb operators Circuits 3: Low rank, arbitrary basis molecular simulations Introduction to OpenFermion Quantum simulation of electronic structure

Args
`operator`	FermionOperator, QubitOperator, DiagonalCoulombHamiltonian, or PolynomialTensor.

Returns
`num_qubits`	`int` The minimum number of qubits on which operator acts.

Returns

num_qubits

int

The minimum number of qubits on which operator acts.

Raises
`TypeError`	Operator of invalid type.

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Last updated 2025-06-06 UTC.