I recently ran into the following issue when I was training a sequence tagger. Does anyone know why this is happening? I use the code in tutorial.

Thanks!
Hi @gccome which version of Flair are you using, and which embeddings? Could you paste the code that you use when you get this error?
I've seen this error while playing around with ELMo Transformer yesterday. It worked before #459, so @gccome could you try to go back to f4a5033a56c0182e73890b9b7247e1e249ad8282 and I think this error message won't appear?
I wasn't able to reproduce it on another (public) dataset, but I'm still searching for a step-by-step example to reproduce.
Hi @alanakbik I was using the most up-to-date Flair code on this repo. For embedding, I tried various combinations, but even the simplest one (only characterembedding) didn't work. Below is my code:
Hi @stefan-it Thanks for the tip. I went back to #450 and the error disappeared. But does it mean I won't be able to use the new release?
# 1. load dataset
corpus = NLPTaskDataFetcher.load_column_corpus(data_folder=data_dir,
column_format=column_format,
train_file=train_filename,
dev_file=val_filename,
test_file=test_filename)
logger.info("Corpus info - {}".format(str(corpus)))
# 2. what tag do we want to predict?
tag_type = 'ner'
# 3. make the tag dictionary from the corpus
tag_dictionary = corpus.make_tag_dictionary(tag_type=tag_type)
logger.info("Tag info - {}".format(str(tag_dictionary.idx2item)))
# 4. initialize embeddings
embedding_types = [
CharacterEmbeddings()
]
# This is my customized embedding, already converted to Gensim format
if custom_embedding_paths is not None:
custom_embeddings = [WordEmbeddings(custom_embedding_path) for custom_embedding_path in custom_embedding_paths]
embedding_types += custom_embeddings
embeddings = StackedEmbeddings(embeddings=embedding_types)
# 5. initialize sequence tagger
tagger = SequenceTagger(hidden_size=hidden_size,
embeddings=embeddings,
tag_dictionary=tag_dictionary,
tag_type=tag_type,
use_crf=use_crf,
use_rnn=True,
rnn_layers=rnn_layers,
dropout=0.0,
word_dropout=0.05,
locked_dropout=0.5
)
# 6. initialize trainer
trainer = ModelTrainer(tagger, corpus, optimizer=Adam)
# 7. start training
training_hist = trainer.train(resource_dir,
learning_rate=learning_rate,
mini_batch_size=mini_batch_size,
eval_mini_batch_size=eval_mini_batch_size,
max_epochs=max_epochs,
anneal_factor=0.5,
patience=patience,
anneal_against_train_loss=False,
train_with_dev=False,
monitor_train=True,
embeddings_in_memory=True,
checkpoint=False,
save_final_model=True,
anneal_with_restarts=False,
test_mode=False,
param_selection_mode=False)
Thanks! Could it be that the error comes from the CharacterEmbeddings class? What if you try a setup with out character embeddings?
@gccome should be fixed now on master - could you check?
Let me check and update you soon.
Hi @alanakbik , thanks for the quick fix! The error disappeared.
Great, thanks for reporting this!