Source code for flwr_datasets.partitioner.iid_partitioner
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"""IID partitioner class that works with Hugging Face Datasets."""
import datasets
from flwr_datasets.partitioner.partitioner import Partitioner
[docs]class IidPartitioner(Partitioner):
"""Partitioner creates each partition sampled randomly from the dataset.
Parameters
----------
num_partitions : int
The total number of partitions that the data will be divided into.
"""
def __init__(self, num_partitions: int) -> None:
super().__init__()
if num_partitions <= 0:
raise ValueError("The number of partitions must be greater than zero.")
self._num_partitions = num_partitions
[docs] def load_partition(self, partition_id: int) -> datasets.Dataset:
"""Load a single IID partition based on the partition index.
Parameters
----------
partition_id : int
the index that corresponds to the requested partition
Returns
-------
dataset_partition : Dataset
single dataset partition
"""
return self.dataset.shard(
num_shards=self._num_partitions, index=partition_id, contiguous=True
)
@property
def num_partitions(self) -> int:
"""Total number of partitions."""
return self._num_partitions