Setting strict=False in QuantumCircuit.assign_parameters has no effect #13933
Description
Environment
- Qiskit version: main @ b9bdc5a
- Python version: Any
- Operating system: Any
What is happening?
Specifying strict=False as part of a QuantumCircuit.assign_parameters call does not ignore provided parameters that do not exist in the circuit (contradicting what the documentation says).
Quoting from the docs:
strict – If False, any parameters given in the mapping that are not used in the circuit will be ignored.
How can we reproduce the issue?
from qiskit.circuit import QuantumCircuit
qc = QuantumCircuit(2)
qc.assign_parameters({"a": 1.0}, strict=False)This produces the error:
Traceback (most recent call last):
File "/home/oss/Files/Dev/Qiskit/qiskit/main/tmp-assign-strict.py", line 4, in <module>
qc.assign_parameters({"a": 1.0}, strict=False)
File "/home/oss/Files/Dev/Qiskit/qiskit/main/qiskit/circuit/quantumcircuit.py", line 4267, in assign_parameters
raw_mapping = parameters if flat_input else self._unroll_param_dict(parameters)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/oss/Files/Dev/Qiskit/qiskit/main/qiskit/circuit/quantumcircuit.py", line 4357, in _unroll_param_dict
out[self.get_parameter(parameter)] = value
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/oss/Files/Dev/Qiskit/qiskit/main/qiskit/circuit/quantumcircuit.py", line 2609, in get_parameter
raise KeyError(f"no parameter named '{name}' is present")
KeyError: "no parameter named 'a' is present"What should happen?
The error should not occur.
Any suggestions?
The strict argument could either be forwarded to QuantumCircuit._unroll_param_dict here:
qiskit/qiskit/circuit/quantumcircuit.py
Line 4267 in b9bdc5a
And then handled inside of that internal method.