qiskit.circuit.QuantumCircuit.reverse_bits¶

QuantumCircuit.reverse_bits()[source]¶

Return a circuit with the opposite order of wires.

The circuit is "vertically" flipped. If a circuit is defined over multiple registers, the resulting circuit will have the same registers but with their order flipped.

This method is useful for converting a circuit written in little-endian convention to the big-endian equivalent, and vice versa.

Returns: the circuit with reversed bit order.
Return type: QuantumCircuit

Examples

input:

     ┌───┐
q_0: ┤ H ├─────■──────
     └───┘┌────┴─────┐
q_1: ─────┤ RX(1.57) ├
          └──────────┘

output:

          ┌──────────┐
q_0: ─────┤ RX(1.57) ├
     ┌───┐└────┬─────┘
q_1: ┤ H ├─────■──────
     └───┘