Spaces:
Runtime error
Runtime error
# coding=utf-8 | |
# Copyright 2019-present, the HuggingFace Inc. team and Facebook, Inc. | |
# | |
# Licensed under the Apache License, Version 2.0 (the "License"); | |
# you may not use this file except in compliance with the License. | |
# You may obtain a copy of the License at | |
# | |
# http://www.apache.org/licenses/LICENSE-2.0 | |
# | |
# Unless required by applicable law or agreed to in writing, software | |
# distributed under the License is distributed on an "AS IS" BASIS, | |
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
# See the License for the specific language governing permissions and | |
# limitations under the License. | |
""" Dataloaders to train DistilBERT | |
adapted in part from Facebook, Inc XLM model (https://github.com/facebookresearch/XLM) | |
""" | |
from typing import List | |
import math | |
from itertools import chain | |
from collections import Counter | |
import numpy as np | |
import torch | |
from utils import logger | |
class Dataset: | |
def __init__(self, | |
params, | |
data): | |
self.params = params | |
self.tokens_per_batch = params.tokens_per_batch | |
self.batch_size = params.batch_size | |
self.shuffle = params.shuffle | |
self.group_by_size = params.group_by_size | |
self.token_ids = np.array(data) | |
self.lengths = np.uint16([len(t) for t in data]) | |
self.check() | |
self.remove_long_sequences() | |
self.remove_empty_sequences() | |
self.check() | |
self.print_statistics() | |
def __len__(self): | |
return len(self.lengths) | |
def check(self): | |
""" | |
Some sanity checks | |
""" | |
assert len(self.token_ids) == len(self.lengths) | |
def remove_long_sequences(self): | |
""" | |
Sequences that are too long are splitted by chunk of max_position_embeddings. | |
""" | |
indices = self.lengths >= self.params.max_position_embeddings | |
logger.info(f'Splitting {sum(indices)} too long sequences.') | |
def divide_chunks(l, n): | |
return [l[i:i + n] for i in range(0, len(l), n)] | |
new_tok_ids = [] | |
new_lengths = [] | |
cls_id, sep_id = self.params.special_tok_ids['cls_token'], self.params.special_tok_ids['sep_token'] | |
max_len = self.params.max_position_embeddings | |
for seq_, len_ in zip(self.token_ids, self.lengths): | |
if len_ <= max_len: | |
new_tok_ids.append(seq_) | |
new_lengths.append(len_) | |
else: | |
sub_seqs = [] | |
for sub_s in divide_chunks(seq_, max_len-2): | |
if sub_s[0] != cls_id: | |
sub_s = np.insert(sub_s, 0, cls_id) | |
if sub_s[-1] != sep_id: | |
sub_s = np.insert(sub_s, len(sub_s), sep_id) | |
assert len(sub_s) <= max_len | |
sub_seqs.append(sub_s) | |
new_tok_ids.extend(sub_seqs) | |
new_lengths.extend([len(l) for l in sub_seqs]) | |
self.token_ids = np.array(new_tok_ids) | |
self.lengths = np.array(new_lengths) | |
def remove_empty_sequences(self): | |
""" | |
Too short sequences are simply removed. This could be tunedd. | |
""" | |
init_size = len(self) | |
indices = self.lengths > 11 | |
self.token_ids = self.token_ids[indices] | |
self.lengths = self.lengths[indices] | |
new_size = len(self) | |
logger.info(f'Remove {init_size - new_size} too short (<=11 tokens) sequences.') | |
def print_statistics(self): | |
""" | |
Print some statistics on the corpus. Only the master process. | |
""" | |
if not self.params.is_master: | |
return | |
logger.info(f'{len(self)} sequences') | |
# data_len = sum(self.lengths) | |
# nb_unique_tokens = len(Counter(list(chain(*self.token_ids)))) | |
# logger.info(f'{data_len} tokens ({nb_unique_tokens} unique)') | |
# unk_idx = self.params.special_tok_ids['unk_token'] | |
# nb_unkown = sum([(t==unk_idx).sum() for t in self.token_ids]) | |
# logger.info(f'{nb_unkown} unknown tokens (covering {100*nb_unkown/data_len:.2f}% of the data)') | |
def select_data(self, a: int, b: int): | |
""" | |
Select a subportion of the data. | |
""" | |
n_sequences = len(self) | |
assert 0 <= a < b <= n_sequences, ValueError(f'`0 <= a < b <= n_sequences` is not met with a={a} and b={b}') | |
logger.info(f'Selecting sequences from {a} to {b} (excluded).') | |
self.token_ids = self.token_ids[a:b] | |
self.lengths = self.lengths[a:b] | |
self.check() | |
def split(self): | |
""" | |
Distributed training: split the data accross the processes. | |
""" | |
assert self.params.n_gpu > 1 | |
logger.info('Splitting the data accross the processuses.') | |
n_seq = len(self) | |
n_seq_per_procesus = n_seq // self.params.world_size | |
a = n_seq_per_procesus * self.params.global_rank | |
b = a + n_seq_per_procesus | |
self.select_data(a=a, b=b) | |
def batch_sequences(self, | |
token_ids: List[List[int]], | |
lengths: List[int]): | |
""" | |
Do the padding and transform into torch.tensor. | |
""" | |
assert len(token_ids) == len(lengths) | |
# Max for paddings | |
max_seq_len_ = max(lengths) | |
# Pad token ids | |
pad_idx = self.params.special_tok_ids['pad_token'] | |
tk_ = [list(t.astype(int)) + [pad_idx]*(max_seq_len_-len(t)) for t in token_ids] | |
assert len(tk_) == len(token_ids) | |
assert all(len(t) == max_seq_len_ for t in tk_) | |
tk_t = torch.tensor(tk_) # (bs, max_seq_len_) | |
lg_t = torch.tensor(lengths.astype(int)) # (bs) | |
return tk_t, lg_t | |
def get_batches_iterator(self, | |
batches): | |
""" | |
Return an iterator over batches. | |
""" | |
for sequences_ids in batches: | |
token_ids, lengths = self.batch_sequences(self.token_ids[sequences_ids], | |
self.lengths[sequences_ids]) | |
yield (token_ids, lengths) | |
def get_iterator(self, | |
seed: int = None): | |
""" | |
Return a data iterator. | |
""" | |
rng = np.random.RandomState(seed) | |
n_sequences = len(self) | |
indices = np.arange(n_sequences) | |
if self.group_by_size: | |
indices = indices[np.argsort(self.lengths[indices], kind='mergesort')] | |
if self.tokens_per_batch == -1: | |
batches = np.array_split(indices, math.ceil(len(indices) * 1. / self.batch_size)) | |
else: | |
assert self.tokens_per_batch > 0 | |
batch_ids = np.cumsum(self.lengths[indices]) // self.tokens_per_batch | |
_, bounds = np.unique(batch_ids, return_index=True) | |
batches = [indices[bounds[i]:bounds[i + 1]] for i in range(len(bounds) - 1)] | |
if bounds[-1] < len(indices): | |
batches.append(indices[bounds[-1]:]) | |
if self.shuffle: | |
rng.shuffle(batches) | |
assert n_sequences == sum([len(x) for x in batches]) | |
assert self.lengths[indices].sum() == sum([self.lengths[x].sum() for x in batches]) | |
return self.get_batches_iterator(batches=batches) | |