Note

This is the documentation for the current state of the development branch of Qiskit Experiments. The documentation or APIs here can change prior to being released.

Calibrations.get_parameter_value

Calibrations.get_parameter_value(param, qubits, schedule=None, valid_only=True, group='default', cutoff_date=None)

Retrieves the value of a parameter.

Parameters may be linked. get_parameter_value() does the following steps:

1. Retrieve the parameter object corresponding to (param, qubits, schedule).

2. The values of this parameter may be stored under another schedule since schedules can share parameters. To deal with this, a list of candidate keys is created internally based on the current configuration.

3. Look for candidate parameter values under the candidate keys.

4. Filter the candidate parameter values according to their date (up until the cutoff_date), validity and calibration group.

5. Return the most recent parameter.

Parameters:

• param (Union[Parameter, str]) – The parameter or the name of the parameter for which to get the parameter value.

• qubits (Union[int, Tuple[int, ...]]) – The qubits for which to get the value of the parameter.

• schedule (Union[ScheduleBlock, str, None]) – The schedule or its name for which to get the parameter value.

• valid_only (bool) – Use only parameters marked as valid.

• group (str) – The calibration group from which to draw the parameters. If not specified this defaults to the ‘default’ group.

• cutoff_date (Optional[datetime]) – Retrieve the most recent parameter up until the cutoff date. Parameters generated after the cutoff date will be ignored. If the cutoff_date is None then all parameters are considered. This allows users to discard more recent values that may be erroneous.

Returns:

The value of the parameter.

Return type:

value

Raises:

CalibrationError – If there is no parameter value for the given parameter name and pulse channel.