OpenXExperienceReplay¶
- class torchrl.data.datasets.OpenXExperienceReplay(dataset_id, batch_size: int | None = None, *, shuffle: bool = True, num_slices: int | None = None, slice_len: int | None = None, pad: float | bool | None = None, replacement: bool = None, streaming: bool | None = None, root: str | Path | None = None, download: bool | None = None, sampler: Sampler | None = None, writer: Writer | None = None, collate_fn: Callable | None = None, pin_memory: bool = False, prefetch: int | None = None, transform: 'torchrl.envs.Transform' | None = None, split_trajs: bool = False, strict_length: bool = True)[source]¶
Open X-Embodiment 資料集的經驗回放。
Open X-Embodiment 資料集包含超過 100 萬條真實機器人軌跡,涵蓋 22 種機器人載體,由 21 家機構合作收集,展示了 527 種技能(160266 項任務)。
網站:https://robotics-transformer-x.github.io/
GitHub:https://github.com/google-deepmind/open_x_embodiment
論文:https://arxiv.org/abs/2310.08864
資料格式遵循 TED 約定。
注意
非張量資料將使用
NonTensorData原語寫入 tensordict 資料中。例如,資料中的 language_instruction 欄位將儲存在 data.get_non_tensor(“language_instruction”) 中(或等效地儲存在 data.get(“language_instruction”).data 中)。有關如何與儲存在TensorDict中的非張量資料互動的更多資訊,請參閱此類的文件。- 引數:
dataset_id (str) – 要下載的資料集。必須是
OpenXExperienceReplay.available_datasets的一部分。batch_size (int) – 取樣期間使用的批次大小。如有必要,可以透過呼叫 data.sample(batch_size) 覆蓋此值。有關更精細的取樣策略,請參閱
num_slices和slice_len關鍵字引數。如果batch_size為None(預設),遍歷資料集將一次提供一條軌跡,而 呼叫sample()仍然需要提供批次大小。
- 關鍵字引數:
shuffle (bool, optional) –
如果為
True,遍歷資料集時,軌跡將以隨機順序提供。如果為False,資料集將以預定義順序遍歷。警告
shuffle=False 也會影響取樣。如果使用者希望在同一程式碼庫中體驗兩種不同的行為(隨機和非隨機),我們建議他們建立一個數據集副本,並將取樣器的
shuffle屬性設定為False。num_slices (int, optional) – 一個批次中的切片數量。這對應於一個批次中存在的軌跡數量。收集後,批次將呈現為子軌跡的連線,可以透過 batch.reshape(num_slices, -1) 恢復。如果提供,batch_size 必須能被 num_slices 整除。此引數與
slice_len互斥。如果num_slices引數等於batch_size,每個樣本將屬於一條不同的軌跡。如果既未提供slice_len也未提供num_slices:每當軌跡長度短於批次大小時,將取樣其長度為 batch_size 的連續切片。如果軌跡長度不足,將引發異常,除非 pad 不是 None。slice_len (int, optional) –
一個批次中的切片長度。這對應於一個批次中存在的軌跡長度。收集後,批次將呈現為子軌跡的連線,可以透過 batch.reshape(-1, slice_len) 恢復。如果提供,batch_size 必須能被 slice_len 整除。此引數與
num_slices互斥。如果slice_len引數等於1,每個樣本將屬於一條不同的軌跡。如果既未提供slice_len也未提供num_slices:每當軌跡長度短於批次大小時,將取樣其長度為 batch_size 的連續切片。如果軌跡長度不足,將引發異常,除非 pad 不是 None。注意
slice_len(但不能使用num_slices)可在遍歷資料集時使用,而無需在建構函式中傳入批次大小。在這些情況下,將選擇軌跡的隨機子序列。replacement (bool, optional) – 如果為
False,將進行無放回取樣。對於已下載資料集預設為True,對於流式資料集預設為False。pad (bool,
floator None) – 如果為True,對於根據 slice_len 或 num_slices 引數長度不足的軌跡,將用 0 填充。如果提供了其他值,將用於填充。如果為False或None(預設),遇到長度不足的軌跡將引發異常。root (Path or str, optional) – OpenX 資料集的根目錄。實際的資料集記憶體對映檔案將儲存在 <root>/<dataset_id> 下。如果未提供,預設為 ~/.cache/torchrl/atari.openx`。
streaming (bool, optional) –
如果為
True,資料將不會被下載,而是從流中讀取。注意
當 download=True 與 streaming=True 相比時,資料的格式__將 改變__。如果資料已下載且取樣器未被觸動(即 num_slices=None、slice_len=None 和 sampler=None),將從資料集中隨機取樣轉換。使用 streaming=True 無法以合理的成本做到這一點:在這種情況下,軌跡將一次一個地被取樣並交付(並進行裁剪以符合批次大小等)。當指定 num_slices 和 slice_len 時,這兩種模式的行為更加相似,因為在這些情況下,兩種情況都會返回子片段的檢視。
download (bool or str, optional) – 如果未找到資料集,是否應該下載。預設為
True。下載也可以傳遞為 “force”,在這種情況下,已下載的資料將被覆蓋。sampler (Sampler, optional) – 要使用的取樣器。如果未提供,將使用預設的 RandomSampler()。
writer (Writer, optional) – 要使用的寫入器。如果未提供,將使用預設的
ImmutableDatasetWriter。collate_fn (callable, optional) – 合併樣本列表以形成 Tensor(s)/輸出的迷你批次。在使用 map-style 資料集進行批次載入時使用。
pin_memory (bool) – 是否應該對 rb 樣本呼叫
pin_memory()。prefetch (int, optional) – 使用多執行緒預取的下一個批次的數量。
transform (Transform, optional) – 呼叫 sample() 時要執行的變換。要鏈式呼叫變換,請使用
Compose類。split_trajs (bool, optional) – 如果為
True,軌跡將沿第一個維度分割並填充以具有匹配的形狀。為了分割軌跡,將使用"done"訊號,該訊號透過done = truncated | terminated恢復。換句話說,假定任何truncated或terminated訊號都等同於軌跡的結束。預設為False。strict_length (bool, optional) – 如果為
False,允許長度短於 slice_len(或 batch_size // num_slices)的軌跡出現在批次中。請注意,這可能導致實際的 batch_size 短於請求的大小!可以使用torchrl.collectors.split_trajectories()分割軌跡。預設為True。
示例
>>> from torchrl.data.datasets import OpenXExperienceReplay >>> import tempfile >>> # Download the data, and sample 128 elements in each batch out of two trajectories >>> num_slices = 2 >>> with tempfile.TemporaryDirectory() as root: ... dataset = OpenXExperienceReplay("cmu_stretch", batch_size=128, ... num_slices=num_slices, download=True, streaming=False, ... root=root, ... ) ... for batch in dataset: ... print(batch.reshape(num_slices, -1)) ... break TensorDict( fields={ action: Tensor(shape=torch.Size([2, 64, 8]), device=cpu, dtype=torch.float64, is_shared=False), discount: Tensor(shape=torch.Size([2, 64]), device=cpu, dtype=torch.float32, is_shared=False), done: Tensor(shape=torch.Size([2, 64, 1]), device=cpu, dtype=torch.bool, is_shared=False), episode: Tensor(shape=torch.Size([2, 64]), device=cpu, dtype=torch.int32, is_shared=False), index: Tensor(shape=torch.Size([2, 64]), device=cpu, dtype=torch.int64, is_shared=False), is_init: Tensor(shape=torch.Size([2, 64]), device=cpu, dtype=torch.bool, is_shared=False), language_embedding: Tensor(shape=torch.Size([2, 64, 512]), device=cpu, dtype=torch.float64, is_shared=False), language_instruction: NonTensorData( data='lift open green garbage can lid', batch_size=torch.Size([2, 64]), device=cpu, is_shared=False), next: TensorDict( fields={ done: Tensor(shape=torch.Size([2, 64, 1]), device=cpu, dtype=torch.bool, is_shared=False), observation: TensorDict( fields={ image: Tensor(shape=torch.Size([2, 64, 3, 128, 128]), device=cpu, dtype=torch.uint8, is_shared=False), state: Tensor(shape=torch.Size([2, 64, 4]), device=cpu, dtype=torch.float64, is_shared=False)}, batch_size=torch.Size([2, 64]), device=cpu, is_shared=False), reward: Tensor(shape=torch.Size([2, 64, 1]), device=cpu, dtype=torch.float32, is_shared=False), terminated: Tensor(shape=torch.Size([2, 64, 1]), device=cpu, dtype=torch.bool, is_shared=False), truncated: Tensor(shape=torch.Size([2, 64, 1]), device=cpu, dtype=torch.bool, is_shared=False)}, batch_size=torch.Size([2, 64]), device=cpu, is_shared=False), observation: TensorDict( fields={ image: Tensor(shape=torch.Size([2, 64, 3, 128, 128]), device=cpu, dtype=torch.uint8, is_shared=False), state: Tensor(shape=torch.Size([2, 64, 4]), device=cpu, dtype=torch.float64, is_shared=False)}, batch_size=torch.Size([2, 64]), device=cpu, is_shared=False), terminated: Tensor(shape=torch.Size([2, 64, 1]), device=cpu, dtype=torch.bool, is_shared=False), truncated: Tensor(shape=torch.Size([2, 64, 1]), device=cpu, dtype=torch.bool, is_shared=False)}, batch_size=torch.Size([2, 64]), device=cpu, is_shared=False) >>> # Read data from a stream. Deliver entire trajectories when iterating >>> dataset = OpenXExperienceReplay("cmu_stretch", ... num_slices=num_slices, download=False, streaming=True) >>> for data in dataset: # data does not have a consistent shape ... break >>> # Define batch-size dynamically >>> data = dataset.sample(128) # delivers 2 sub-trajectories of length 64
- add(data: TensorDictBase) int¶
向經驗回放緩衝區新增一個元素。
- 引數:
data (Any) – 要新增到經驗回放緩衝區的資料
- 返回:
資料在經驗回放緩衝區中的索引。
- append_transform(transform: Transform, *, invert: bool = False) ReplayBuffer¶
在末尾新增變換。
呼叫 sample 時,變換按順序應用。
- 引數:
transform (Transform) – 要新增的變換
- 關鍵字引數:
invert (bool, optional) – 如果為
True,變換將被反轉(寫入期間呼叫 forward,讀取期間呼叫 inverse)。預設為False。
示例
>>> rb = ReplayBuffer(storage=LazyMemmapStorage(10), batch_size=4) >>> data = TensorDict({"a": torch.zeros(10)}, [10]) >>> def t(data): ... data += 1 ... return data >>> rb.append_transform(t, invert=True) >>> rb.extend(data) >>> assert (data == 1).all()
- property data_path¶
資料集路徑,包括分割資訊。
- property data_path_root¶
資料集根目錄路徑。
- delete()¶
從磁碟刪除資料集儲存。
- dumps(path)¶
將經驗回放緩衝區儲存到指定路徑的磁碟上。
- 引數:
path (Path or str) – 儲存經驗回放緩衝區的路徑。
示例
>>> import tempfile >>> import tqdm >>> from torchrl.data import LazyMemmapStorage, TensorDictReplayBuffer >>> from torchrl.data.replay_buffers.samplers import PrioritizedSampler, RandomSampler >>> import torch >>> from tensordict import TensorDict >>> # Build and populate the replay buffer >>> S = 1_000_000 >>> sampler = PrioritizedSampler(S, 1.1, 1.0) >>> # sampler = RandomSampler() >>> storage = LazyMemmapStorage(S) >>> rb = TensorDictReplayBuffer(storage=storage, sampler=sampler) >>> >>> for _ in tqdm.tqdm(range(100)): ... td = TensorDict({"obs": torch.randn(100, 3, 4), "next": {"obs": torch.randn(100, 3, 4)}, "td_error": torch.rand(100)}, [100]) ... rb.extend(td) ... sample = rb.sample(32) ... rb.update_tensordict_priority(sample) >>> # save and load the buffer >>> with tempfile.TemporaryDirectory() as tmpdir: ... rb.dumps(tmpdir) ... ... sampler = PrioritizedSampler(S, 1.1, 1.0) ... # sampler = RandomSampler() ... storage = LazyMemmapStorage(S) ... rb_load = TensorDictReplayBuffer(storage=storage, sampler=sampler) ... rb_load.loads(tmpdir) ... assert len(rb) == len(rb_load)
- empty()¶
清空經驗回放緩衝區並將遊標重置為 0。
- extend(tensordicts: TensorDictBase) Tensor¶
使用迭代器中包含的一個或多個元素擴充套件經驗回放緩衝區。
如果存在,將呼叫逆變換。
- 引數:
data (iterable) – 要新增到經驗回放緩衝區的資料集合。
- 返回:
新增到經驗回放緩衝區的資料的索引。
警告
extend()在處理值列表時可能具有模糊的簽名,這些值列表應被解釋為 PyTree(在這種情況下,列表中的所有元素將被放入儲存中儲存的 PyTree 的一個切片中)或要逐個新增的值列表。為了解決這個問題,TorchRL 明確區分了 list 和 tuple:tuple 將被視為 PyTree,list(在根級別)將被解釋為要逐個新增到緩衝區的值堆疊。對於ListStorage例項,只能提供未繫結的元素(不能提供 PyTrees)。
- insert_transform(index: int, transform: Transform, *, invert: bool = False) ReplayBuffer¶
插入變換。
呼叫 sample 時,變換按順序執行。
- 引數:
index (int) – 插入變換的位置。
transform (Transform) – 要新增的變換
- 關鍵字引數:
invert (bool, optional) – 如果為
True,變換將被反轉(寫入期間呼叫 forward,讀取期間呼叫 inverse)。預設為False。
- loads(path)¶
從給定路徑載入經驗回放緩衝區狀態。
緩衝區應具有匹配的元件並使用
dumps()儲存。- 引數:
path (Path or str) – 經驗回放緩衝區儲存的路徑。
有關更多資訊,請參閱
dumps()。
- preprocess(fn: Callable[[TensorDictBase], TensorDictBase], dim: int = 0, num_workers: int | None = None, *, chunksize: int | None = None, num_chunks: int | None = None, pool: mp.Pool | None = None, generator: torch.Generator | None = None, max_tasks_per_child: int | None = None, worker_threads: int = 1, index_with_generator: bool = False, pbar: bool = False, mp_start_method: str | None = None, num_frames: int | None = None, dest: str | Path) TensorStorage¶
預處理資料集並返回包含格式化資料的新儲存。
資料轉換必須是單元的(作用於資料集的單個樣本)。
引數和關鍵字引數將轉發給
map()。隨後可以使用
delete()刪除資料集。- 關鍵字引數:
dest (path 或 等效型別) – 新資料集的儲存位置路徑。
num_frames (int, 可選) – 如果提供,將僅轉換前 num_frames 個幀。這對於初步除錯轉換很有用。
返回: 可在
ReplayBuffer例項中使用的新的儲存。示例
>>> from torchrl.data.datasets import MinariExperienceReplay >>> >>> data = MinariExperienceReplay( ... list(MinariExperienceReplay.available_datasets)[0], ... batch_size=32 ... ) >>> print(data) MinariExperienceReplay( storages=TensorStorage(TensorDict( fields={ action: MemoryMappedTensor(shape=torch.Size([1000000, 8]), device=cpu, dtype=torch.float32, is_shared=True), episode: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.int64, is_shared=True), info: TensorDict( fields={ distance_from_origin: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), forward_reward: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), goal: MemoryMappedTensor(shape=torch.Size([1000000, 2]), device=cpu, dtype=torch.float64, is_shared=True), qpos: MemoryMappedTensor(shape=torch.Size([1000000, 15]), device=cpu, dtype=torch.float64, is_shared=True), qvel: MemoryMappedTensor(shape=torch.Size([1000000, 14]), device=cpu, dtype=torch.float64, is_shared=True), reward_ctrl: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), reward_forward: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), reward_survive: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), success: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.bool, is_shared=True), x_position: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), x_velocity: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), y_position: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), y_velocity: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False), next: TensorDict( fields={ done: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.bool, is_shared=True), info: TensorDict( fields={ distance_from_origin: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), forward_reward: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), goal: MemoryMappedTensor(shape=torch.Size([1000000, 2]), device=cpu, dtype=torch.float64, is_shared=True), qpos: MemoryMappedTensor(shape=torch.Size([1000000, 15]), device=cpu, dtype=torch.float64, is_shared=True), qvel: MemoryMappedTensor(shape=torch.Size([1000000, 14]), device=cpu, dtype=torch.float64, is_shared=True), reward_ctrl: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), reward_forward: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), reward_survive: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), success: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.bool, is_shared=True), x_position: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), x_velocity: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), y_position: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), y_velocity: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False), observation: TensorDict( fields={ achieved_goal: MemoryMappedTensor(shape=torch.Size([1000000, 2]), device=cpu, dtype=torch.float64, is_shared=True), desired_goal: MemoryMappedTensor(shape=torch.Size([1000000, 2]), device=cpu, dtype=torch.float64, is_shared=True), observation: MemoryMappedTensor(shape=torch.Size([1000000, 27]), device=cpu, dtype=torch.float64, is_shared=True)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False), reward: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.float64, is_shared=True), terminated: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.bool, is_shared=True), truncated: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.bool, is_shared=True)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False), observation: TensorDict( fields={ achieved_goal: MemoryMappedTensor(shape=torch.Size([1000000, 2]), device=cpu, dtype=torch.float64, is_shared=True), desired_goal: MemoryMappedTensor(shape=torch.Size([1000000, 2]), device=cpu, dtype=torch.float64, is_shared=True), observation: MemoryMappedTensor(shape=torch.Size([1000000, 27]), device=cpu, dtype=torch.float64, is_shared=True)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False)), samplers=RandomSampler, writers=ImmutableDatasetWriter(), batch_size=32, transform=Compose( ), collate_fn=<function _collate_id at 0x120e21dc0>) >>> from torchrl.envs import CatTensors, Compose >>> from tempfile import TemporaryDirectory >>> >>> cat_tensors = CatTensors( ... in_keys=[("observation", "observation"), ("observation", "achieved_goal"), ... ("observation", "desired_goal")], ... out_key="obs" ... ) >>> cat_next_tensors = CatTensors( ... in_keys=[("next", "observation", "observation"), ... ("next", "observation", "achieved_goal"), ... ("next", "observation", "desired_goal")], ... out_key=("next", "obs") ... ) >>> t = Compose(cat_tensors, cat_next_tensors) >>> >>> def func(td): ... td = td.select( ... "action", ... "episode", ... ("next", "done"), ... ("next", "observation"), ... ("next", "reward"), ... ("next", "terminated"), ... ("next", "truncated"), ... "observation" ... ) ... td = t(td) ... return td >>> with TemporaryDirectory() as tmpdir: ... new_storage = data.preprocess(func, num_workers=4, pbar=True, mp_start_method="fork", dest=tmpdir) ... rb = ReplayBuffer(storage=new_storage) ... print(rb) ReplayBuffer( storage=TensorStorage( data=TensorDict( fields={ action: MemoryMappedTensor(shape=torch.Size([1000000, 8]), device=cpu, dtype=torch.float32, is_shared=True), episode: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.int64, is_shared=True), next: TensorDict( fields={ done: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.bool, is_shared=True), obs: MemoryMappedTensor(shape=torch.Size([1000000, 31]), device=cpu, dtype=torch.float64, is_shared=True), observation: TensorDict( fields={ }, batch_size=torch.Size([1000000]), device=cpu, is_shared=False), reward: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.float64, is_shared=True), terminated: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.bool, is_shared=True), truncated: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.bool, is_shared=True)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False), obs: MemoryMappedTensor(shape=torch.Size([1000000, 31]), device=cpu, dtype=torch.float64, is_shared=True), observation: TensorDict( fields={ }, batch_size=torch.Size([1000000]), device=cpu, is_shared=False)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False), shape=torch.Size([1000000]), len=1000000, max_size=1000000), sampler=RandomSampler(), writer=RoundRobinWriter(cursor=0, full_storage=True), batch_size=None, collate_fn=<function _collate_id at 0x168406fc0>)
- register_load_hook(hook: Callable[[Any], Any])¶
註冊儲存的載入鉤子。
注意
鉤子目前在儲存回放緩衝區時不會被序列化:每次建立緩衝區時必須手動重新初始化它們。
- register_save_hook(hook: Callable[[Any], Any])¶
註冊儲存的儲存鉤子。
注意
鉤子目前在儲存回放緩衝區時不會被序列化:每次建立緩衝區時必須手動重新初始化它們。
- sample(batch_size: int | None = None, return_info: bool = False, include_info: bool = None) TensorDictBase¶
從回放緩衝區中取樣一批資料。
使用 Sampler 取樣索引,並從 Storage 中檢索它們。
- 引數:
batch_size (int, 可選) – 要收集的資料大小。如果未提供,此方法將按取樣器指示的批次大小進行取樣。
return_info (bool) – 是否返回資訊 (info)。如果為 True,結果為元組 (data, info)。如果為 False,結果為 data。
- 返回:
一個 TensorDict,包含在回放緩衝區中選擇的一批資料。如果 return_info 標誌設定為 True,則是一個包含此 TensorDict 和 info 的元組。
- set_storage(storage: Storage, collate_fn: Callable | None = None)¶
在回放緩衝區中設定新的儲存並返回之前的儲存。
- 引數:
storage (Storage) – 緩衝區的新儲存。
collate_fn (callable, 可選) – 如果提供,則將 collate_fn 設定為此值。否則,它將被重置為預設值。
- property write_count¶
透過 add 和 extend 方法已寫入緩衝區的總條目數。