forked from mindspore-Ecosystem/mindspore
26 lines
1.3 KiB
ReStructuredText
26 lines
1.3 KiB
ReStructuredText
|
Class mindspore.dataset.WeightedRandomSampler(weights, num_samples=None, replacement=True)
|
|||
|
|
|
|||
|
|
使用给定的权重（概率）进行随机采样[0，len(weights) - 1]中的元素。
|
|||
|
|
|
|||
|
|
参数：
|
|||
|
|
weights (list[float, int])：权重序列，总和不一定为1。
|
|||
|
|
num_samples (int, optional)：待采样的元素数量（默认值为None，代表采样所有元素）。
|
|||
|
|
replacement (bool)：如果值为True，则将样本ID放回下一次采样（默认值为True）。
|
|||
|
|
|
|||
|
|
示例：
|
|||
|
|
>>> weights = [0.9, 0.01, 0.4, 0.8, 0.1, 0.1, 0.3]
|
|||
|
|
>>>
|
|||
|
|
>>> # creates a WeightedRandomSampler that will sample 4 elements without replacement
|
|||
|
|
>>> sampler = ds.WeightedRandomSampler(weights, 4)
|
|||
|
|
>>> dataset = ds.ImageFolderDataset(image_folder_dataset_dir,
|
|||
|
|
... num_parallel_workers=8,
|
|||
|
|
... sampler=sampler)
|
|||
|
|
|
|||
|
|
异常：
|
|||
|
|
TypeError：weights元素的类型不是number。
|
|||
|
|
TypeError：num_samples不是整数值。
|
|||
|
|
TypeError：replacement不是布尔值。
|
|||
|
|
RuntimeError：weights为空或全为零。
|
|||
|
|
ValueError：num_samples为负值。
|
|||
|
|
|
|||
|
|
.. include:: mindspore.dataset.BuiltinSampler.rst
|