sequence_min_length_ratios for qiskit.transpiler.passes.PadDynamicalDecoupling

[Arianvezvaee]

What should we add?

In the old version of PadDynamicalDecoupling there was an option sequence_min_length_ratios that allowed for inserting different sequences with shorter or longer delay times, set by the ratio of the delay time to the idling gap. This seems to have been removed/missing from the new PadDynamicalDecoupling. Is there a way to use this feature in this new version? Thank you!

[Arianvezvaee]

Update: The feature can be added by adding the following to the _pad() function, and updating the __init__

`# Ensure idle time is long enough for DD
if time_interval < self._sequence_min_length_ratios * np.sum(self._dd_sequence_lengths[qubit]):
# If idle time is too short, insert only a delay
self._apply_scheduled_op(dag, t_start, Delay(time_interval, dag.unit), qubit)
return

slack = time_interval - np.sum(self._dd_sequence_lengths[qubit])
sequence_gphase = self._sequence_phase
`