def create(cls, train_ds, valid_ds, test_ds=None, path='.',
bs=64, equal_lengths=True, length_col=None, tfms=None, **kwargs):
if equal_lengths:
return super().create(train_ds, valid_ds, test_ds=test_ds, path=path,
bs=bs, dl_tfms=tfms, **kwargs)
else:
datasets = super()._init_ds(train_ds, valid_ds, test_ds)
train_ds, valid_ds, fix_ds = datasets[:3]
if len(datasets) == 4:
test_ds = datasets[3]
train_lengths = train_ds.lengths(length_col)
train_sampler = SortishSampler(train_ds.x, key=lambda i: train_lengths[i], bs=bs//2)
train_dl = DataLoader(train_ds, batch_size=bs, sampler=train_sampler, **kwargs)
# precalculate lengths ahead of time if they aren't included in xtra
valid_lengths = valid_ds.lengths(length_col)
valid_sampler = SortSampler(valid_ds.x, key=lambda i: valid_lengths[i])
valid_dl = DataLoader(valid_ds, batch_size=bs, sampler=valid_sampler, **kwargs)
fix_lengths = fix_ds.lengths(length_col)
fix_sampler = SortSampler(fix_ds.x, key=lambda i: fix_lengths[i])
fix_dl = DataLoader(fix_ds, batch_size=bs, sampler=fix_sampler, **kwargs)
dataloaders = [train_dl, valid_dl, fix_dl]
if test_ds is not None:
test_dl = DataLoader(test_ds, batch_size=1, **kwargs)
dataloaders.append(test_dl)
return cls(*dataloaders, path=path, collate_fn=pad_collate1d, tfms=tfms)
def test_sortish_sampler_sorts_each_batch_descending():
bs = 4
n = bs * 100
data = 2 * np.arange(n)
samp = list(SortishSampler(data, lambda i: data[i], bs))
# The sample is a permutation of the indices.
assert sorted(samp) == list(range(n))
# And that permutation is kind of reverse sorted.
assert all(s1 > s2 or (i + 1) % bs == 0 # don't check batch boundaries
for i, (s1, s2) in enumerate(zip(samp, samp[1:])))
assert samp[0] == max(samp)
def load_training_and_validation_data(self,
training_data_ids_path,
training_data_labels_path,
validation_data_ids_path,
validation_data_labels_path,
classifier_data_dir,
batch_size=10):
training_token_ids = np.load(training_data_ids_path)
validation_token_ids = np.load(validation_data_ids_path)
training_labels = np.load(training_data_labels_path)
validation_labels = np.load(validation_data_labels_path)
training_labels = training_labels.flatten()
validation_labels = validation_labels.flatten()
training_labels -= training_labels.min()
validation_labels -= validation_labels.min()
training_dataset = TextDataset(training_token_ids, training_labels)
validation_dataset = TextDataset(validation_token_ids,
validation_labels)
training_data_sampler = SortishSampler(
data_source=training_token_ids,
key=lambda x: len(training_token_ids[x]),
bs=batch_size // 2)
validation_data_sampler = SortSampler(
data_source=validation_token_ids,
key=lambda x: len(validation_token_ids[x]))
training_dataloader = DataLoader(dataset=training_dataset,
batch_size=batch_size // 2,
transpose=True,
num_workers=1,
pad_idx=1,
sampler=training_data_sampler)
validation_dataloader = DataLoader(dataset=validation_dataset,
batch_size=batch_size,
transpose=True,
num_workers=1,
pad_idx=1,
sampler=validation_data_sampler)
self.model_data = ModelData(path=classifier_data_dir,
trn_dl=training_dataloader,
val_dl=validation_dataloader)
def create(cls,
train_ds,
valid_ds,
test_ds=None,
path='.',
bs=64,
equal_lengths=True,
tfms=None,
**kwargs):
if equal_lengths:
return super().create(train_ds,
valid_ds,
test_ds=test_ds,
path=path,
bs=bs,
tfms=tfms,
**kwargs)
else:
datasets = [train_ds, valid_ds]
if test_ds is not None:
datasets.append(test_ds)
train_sampler = SortishSampler(
datasets[0].x,
key=lambda i: datasets[0][i][0].data.shape[0],
bs=bs)
train_dl = DataLoader(datasets[0],
batch_size=bs,
sampler=train_sampler,
**kwargs)
dataloaders = [train_dl]
for ds in datasets[1:]:
sampler = SortSampler(ds.x,
key=lambda i: ds[i][0].data.shape[0])
dataloaders.append(
DataLoader(ds, batch_size=bs, sampler=sampler, **kwargs))
return cls(*dataloaders,
path=path,
collate_fn=pad_collate,
tfms=tfms)
def _train_classifier(self,
train_ids,
train_labels,
batch_size=4,
val_ids=None,
val_labels=None):
# change from multi-label to multi-class:
def one_hot_idxs(idxs, n_classes):
res = np.zeros(n_classes)
res[idxs] = 1.
return res
onehot_train_labels = np.array(
[one_hot_idxs(l, self._n_classes) for l in train_labels])
onehot_val_labels = np.array(
[one_hot_idxs(l, self._n_classes) for l in val_labels])
train_ds = TextDataset(train_ids, onehot_train_labels)
val_ds = TextDataset(val_ids, onehot_val_labels)
train_sampler = SortishSampler(train_ids,
key=lambda x: len(train_ids[x]),
bs=batch_size)
val_sampler = SortSampler(val_ids, key=lambda x: len(val_ids[x]))
train_dl = DataLoader(train_ds,
batch_size,
num_workers=1,
transpose=True,
pad_idx=1,
sampler=train_sampler)
val_dl = DataLoader(val_ds,
batch_size,
num_workers=1,
transpose=True,
pad_idx=1,
sampler=val_sampler)
md = ModelData("tmp", train_dl, val_dl)
m = get_rnn_classifier(
self._bptt,
20 * 70,
self._n_classes,
self._vocab.size,
emb_sz=self._embedding_size,
n_hid=self._n_hidden_activations,
n_layers=self._n_layers,
pad_token=1,
layers=[self._embedding_size * 3, 128, self._n_classes],
drops=[self._dropouts_classifier[4], 0.1],
dropouti=self._dropouts_classifier[0],
wdrop=self._dropouts_classifier[1],
dropoute=self._dropouts_classifier[2],
dropouth=self._dropouts_classifier[3])
self._classifier_model = RNN_Learner(md,
TextModel(to_gpu(m)),
opt_fn=self.OPT_FN)
self._classifier_model.reg_fn = partial(seq2seq_reg, alpha=2, beta=1)
self._classifier_model.clip = 25. # or 0.3 ?!
def binary_ce_wrapper(predicted, gt):
out = F.sigmoid(predicted)
return binary_cross_entropy(out, gt)
self._classifier_model.crit = binary_ce_wrapper
jaccard_0_5 = partial(self.func_metric, func=jaccard_index)
jaccard_0_5.__name__ = "jaccard_0_5"
precision_0_5 = partial(self.func_metric, func=precision)
precision_0_5.__name__ = "precision_0_5"
recall_0_5 = partial(self.func_metric, func=recall)
recall_0_5.__name__ = "recall_0_5"
f1_0_5 = partial(self.func_metric, func=f1)
f1_0_5.__name__ = "f1_0_5"
self._classifier_model.metrics = [
jaccard_0_5, precision_0_5, recall_0_5, f1_0_5
]
lr = 3e-3
lrm = 2.6
lrs = np.array(
[lr / (lrm**4), lr / (lrm**3), lr / (lrm**2), lr / lrm, lr])
self._classifier_model.load_encoder('enc_weights')
self._classifier_model.freeze_to(-1)
self._classifier_model.fit(
lrs,
1,
cycle_len=1,
use_clr=(8, 3),
callbacks=[LoggingCallback(save_path="./tmp/log")])
self._classifier_model.freeze_to(-2)
self._classifier_model.fit(
lrs,
1,
cycle_len=1,
use_clr=(8, 3),
callbacks=[LoggingCallback(save_path="./tmp/log")])
self._classifier_model.unfreeze()
self._classifier_model.fit(
lrs,
1,
cycle_len=24,
use_clr=(32, 10),
callbacks=[LoggingCallback(save_path="./tmp/log")])
self._classifier_model.save('classifier_weights')
df.loc[df.rating > 3, "label"] = 2
# In[18]:
df_train.label.value_counts()
# In[19]:
bs = 64
trn_ds = TextDataset(tokens_train, df_train.label.values)
val_ds = TextDataset(tokens_val, df_val.label.values)
trn_samp = SortishSampler(tokens_train, key=lambda x: len(tokens_train[x]), bs=bs//2)
val_samp = SortSampler(tokens_val, key=lambda x: len(tokens_val[x]))
trn_dl = DataLoader(trn_ds, bs//2, transpose=False, num_workers=1, pad_idx=2, sampler=trn_samp)
val_dl = DataLoader(val_ds, bs, transpose=False, num_workers=1, pad_idx=2, sampler=val_samp)
model_data = ModelData(path, trn_dl, val_dl)
# In[20]:
model= get_transformer_classifier(
n_tok=n_toks,
emb_sz=EMB_DIM,
n_head=12,
n_layer=3,
n_ctx=200,