Source code for

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# coding: utf-8
# pylint: disable=
"""Dataset sampler."""
__all__ = ['IntervalSampler']

from import sampler

[docs]class IntervalSampler(sampler.Sampler): """Samples elements from [0, length) at fixed intervals. Parameters ---------- length : int Length of the sequence. interval : int The number of items to skip between two samples. rollover : bool, default True Whether to start again from the first skipped item after reaching the end. If true, this sampler would start again from the first skipped item until all items are visited. Otherwise, iteration stops when end is reached and skipped items are ignored. Examples -------- >>> sampler =, interval=3) >>> list(sampler) [0, 3, 6, 9, 12, 1, 4, 7, 10, 2, 5, 8, 11] >>> sampler =, interval=3, rollover=False) >>> list(sampler) [0, 3, 6, 9, 12] """ def __init__(self, length, interval, rollover=True): assert interval <= length, \ "Interval {} must be smaller than or equal to length {}".format(interval, length) self._length = length self._interval = interval self._rollover = rollover def __iter__(self): for i in range(self._interval if self._rollover else 1): for j in range(i, self._length, self._interval): yield j def __len__(self): return self._length