fiftyone.core.utils.LatencyDynamicBatcher

Class for iterating over the elements of an iterable with a dynamic batch size to achieve a desired latency.

The batch sizes emitted when iterating over this object are dynamically scaled such that the latency between next() calls is as close as possible to a specified target latency.

This class is often used in conjunction with a ProgressBar to keep the user appraised on the status of a long-running task.

Example usage:

import fiftyone.core.utils as fou

elements = range(int(1e7))

batcher = fou.LatencyDynamicBatcher(
    elements, target_latency=0.1, max_batch_beta=2.0
)

for batch in batcher:
    print("batch size: %d" % len(batch))

batcher = fou.LatencyDynamicBatcher(
    elements,
    target_latency=0.1,
    max_batch_beta=2.0,
    progress=True,
)

with batcher:
    for batch in batcher:
        print("batch size: %d" % len(batch))