qemcmc.coarse_grain

Classes

CoarseGraining

CoarseGraining class to generate partitions of spins for quantum proposals.

Module Contents

class qemcmc.coarse_grain.CoarseGraining(n, subgroups=None, subgroup_probs=None, repeated=True)

CoarseGraining class to generate partitions of spins for quantum proposals.

Parameters:

• n (int) – Number of spins in the system.

• subgroups (list[list[int]], optional) – A list of subgroups, where each subgroup is a list of spin indices. If None, the entire set of spins is treated as one subgroup.

• subgroup_probs (list[float], optional) – A list of probabilities corresponding to each subgroup, used for weighted random selection. Must sum to 1. If None, subgroups are selected uniformly at random.

• repeated (bool, optional) – If True, then multiple subgroups are run on the quantum computer in serial, if not then only one subgroup is selected at random and run on the quantum computer. Default is True.

_user_specified

n

subgroups = None

subgroup_probs = None

repeated = True

sample() → list[int]

Randomly samples a subgroup according to the specified probability distribution.

get_partitions(m: int) → list[list[int]]

Returns partitions of spins for sequential quantum updates.

If the user provided explicit subgroups at initialisation, those are returned directly (all if repeated=True, otherwise just the first). If no subgroups were specified, random disjoint partitions of approximate size n/m are generated.

Parameters:

m (int) – The number of partitions to generate. Ignored if user-specified subgroups are provided.