text
stringlengths 1
1.02k
| class_index
int64 0
10.8k
| source
stringlengths 85
188
|
|---|---|---|
>>> # However, with temperature close to 0, it approximates greedy decoding strategies (invariant)
>>> generate_kwargs["temperature"] = 0.0001
>>> outputs = model.generate(**inputs, **generate_kwargs)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True))
['Hugging Face Company is a company that has been around for over 20 years',
'Hugging Face Company is a company that has been around for over 20 years']
```
"""
def __init__(self, temperature: float):
if not isinstance(temperature, float) or not (temperature > 0):
except_msg = (
f"`temperature` (={temperature}) has to be a strictly positive float, otherwise your next token "
"scores will be invalid."
)
if isinstance(temperature, float) and temperature == 0.0:
except_msg += " If you're looking for greedy decoding strategies, set `do_sample=False`."
raise ValueError(except_msg)
| 10,667 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
self.temperature = temperature
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
scores_processed = scores / self.temperature
return scores_processed
| 10,667 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class RepetitionPenaltyLogitsProcessor(LogitsProcessor):
r"""
[`LogitsProcessor`] that prevents the repetition of previous tokens through a penalty. This penalty is applied at
most once per token. Note that, for decoder-only models like most LLMs, the considered tokens include the prompt.
In the original [paper](https://arxiv.org/pdf/1909.05858.pdf), the authors suggest the use of a penalty of around
1.2 to achieve a good balance between truthful generation and lack of repetition. To penalize and reduce
repetition, use `penalty` values above 1.0, where a higher value penalizes more strongly. To reward and encourage
repetition, use `penalty` values between 0.0 and 1.0, where a lower value rewards more strongly.
Args:
penalty (`float`):
The parameter for repetition penalty. 1.0 means no penalty. Above 1.0 penalizes previously generated
tokens. Between 0.0 and 1.0 rewards previously generated tokens.
Examples:
| 10,668 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
```py
>>> from transformers import AutoTokenizer, AutoModelForCausalLM
>>> # Initializing the model and tokenizer for it
>>> model = AutoModelForCausalLM.from_pretrained("distilbert/distilgpt2")
>>> tokenizer = AutoTokenizer.from_pretrained("distilbert/distilgpt2")
>>> inputs = tokenizer(["I'm not going to"], return_tensors="pt")
>>> # This shows a normal generate without any specific parameters
>>> summary_ids = model.generate(**inputs)
>>> print(tokenizer.batch_decode(summary_ids, skip_special_tokens=True)[0])
I'm not going to be able to do that. I'm going to be able to do that
>>> # This generates a penalty for repeated tokens
>>> penalized_ids = model.generate(**inputs, repetition_penalty=1.1)
>>> print(tokenizer.batch_decode(penalized_ids, skip_special_tokens=True)[0])
I'm not going to be able to do that. I'll just have to go out and play
```
"""
| 10,668 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
def __init__(self, penalty: float):
if not isinstance(penalty, float) or not (penalty > 0):
raise ValueError(f"`penalty` has to be a strictly positive float, but is {penalty}")
self.penalty = penalty
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
score = torch.gather(scores, 1, input_ids)
# if score < 0 then repetition penalty has to be multiplied to reduce the token probabilities
score = torch.where(score < 0, score * self.penalty, score / self.penalty)
scores_processed = scores.scatter(1, input_ids, score)
return scores_processed
| 10,668 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class EncoderRepetitionPenaltyLogitsProcessor(LogitsProcessor):
r"""
[`LogitsProcessor`] that works similarly to [`RepetitionPenaltyLogitsProcessor`], but with an *inverse* penalty
that is applied to the tokens present in the prompt. In other words, a penalty above 1.0 increases the odds of
selecting tokens that were present in the prompt.
It was designed to avoid hallucination in input-grounded tasks, like summarization. Although originally intended
for encoder-decoder models, it can also be used with decoder-only models like LLMs.
Args:
penalty (`float`):
The parameter for repetition penalty. 1.0 means no penalty. Above 1.0 rewards prompt tokens. Between 0.0
and 1.0 penalizes prompt tokens.
encoder_input_ids (`torch.LongTensor`):
The encoder_input_ids that should be repeated within the decoder ids.
Examples:
```python
>>> from transformers import AutoModelForCausalLM, AutoTokenizer
| 10,669 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> tokenizer = AutoTokenizer.from_pretrained("bigscience/bloomz-560m")
>>> model = AutoModelForCausalLM.from_pretrained("bigscience/bloomz-560m")
>>> inputs = tokenizer(["Alice and Bob. The third member's name was"], return_tensors="pt")
>>> gen_out = model.generate(**inputs)
>>> print(tokenizer.batch_decode(gen_out, skip_special_tokens=True)[0])
Alice and Bob. The third member's name was not mentioned.
>>> # With the `encoder_repetition_penalty` argument we can trigger this logits processor in `generate`, which can
>>> # promote the use of prompt tokens ("Bob" in this example)
>>> gen_out = model.generate(**inputs, encoder_repetition_penalty=1.2)
>>> print(tokenizer.batch_decode(gen_out, skip_special_tokens=True)[0])
Alice and Bob. The third member's name was Bob. The third member's name was Bob.
```
"""
| 10,669 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
def __init__(self, penalty: float, encoder_input_ids: torch.LongTensor):
if not isinstance(penalty, float) or not (penalty > 0):
raise ValueError(f"`penalty` has to be a strictly positive float, but is {penalty}")
self.penalty = 1 / penalty
self.encoder_input_ids = encoder_input_ids
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
score = torch.gather(scores, 1, self.encoder_input_ids)
# if score < 0 then hallucination penalty has to be multiplied to increase the token probabilities
score = torch.where(score < 0, score * self.penalty, score / self.penalty)
scores_processed = scores.scatter(1, self.encoder_input_ids, score)
return scores_processed
| 10,669 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class TopPLogitsWarper(LogitsProcessor):
"""
[`LogitsProcessor`] that performs top-p, i.e. restricting to top tokens summing to prob_cut_off <= prob_cut_off.
Often used together with [`TemperatureLogitsWarper`] and [`TopKLogitsWarper`].
Args:
top_p (`float`):
If set to < 1, only the smallest set of most probable tokens with probabilities that add up to `top_p` or
higher are kept for generation.
filter_value (`float`, *optional*, defaults to -inf):
All filtered values will be set to this float value.
min_tokens_to_keep (`int`, *optional*, defaults to 1):
Minimum number of tokens that cannot be filtered.
Examples:
```python
>>> from transformers import AutoTokenizer, AutoModelForCausalLM, set_seed
>>> set_seed(1)
>>> model = AutoModelForCausalLM.from_pretrained("distilbert/distilgpt2")
>>> tokenizer = AutoTokenizer.from_pretrained("distilbert/distilgpt2")
| 10,670 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> inputs = tokenizer("A sequence: 1, 2", return_tensors="pt")
>>> # With sampling, the output is unexpected -- sometimes too unexpected.
>>> outputs = model.generate(**inputs, do_sample=True)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
A sequence: 1, 2, 3 | < 4 (left-hand pointer) ;
<BLANKLINE>
<BLANKLINE>
>>> # With `top_p` sampling, the output gets restricted to high-probability tokens.
>>> # Pro tip: In practice, LLMs use `top_p` in the 0.9-0.95 range.
>>> outputs = model.generate(**inputs, do_sample=True, top_p=0.1)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
A sequence: 1, 2, 3, 4, 5, 6, 7, 8, 9
```
"""
| 10,670 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
def __init__(self, top_p: float, filter_value: float = -float("Inf"), min_tokens_to_keep: int = 1):
top_p = float(top_p)
if top_p < 0 or top_p > 1.0:
raise ValueError(f"`top_p` has to be a float > 0 and < 1, but is {top_p}")
if not isinstance(min_tokens_to_keep, int) or (min_tokens_to_keep < 1):
raise ValueError(f"`min_tokens_to_keep` has to be a positive integer, but is {min_tokens_to_keep}")
self.top_p = top_p
self.filter_value = filter_value
self.min_tokens_to_keep = min_tokens_to_keep
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
sorted_logits, sorted_indices = torch.sort(scores, descending=False)
cumulative_probs = sorted_logits.softmax(dim=-1).cumsum(dim=-1)
| 10,670 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
# Remove tokens with cumulative top_p above the threshold (token with 0 are kept)
sorted_indices_to_remove = cumulative_probs <= (1 - self.top_p)
# Keep at least min_tokens_to_keep
sorted_indices_to_remove[..., -self.min_tokens_to_keep :] = 0
# scatter sorted tensors to original indexing
indices_to_remove = sorted_indices_to_remove.scatter(1, sorted_indices, sorted_indices_to_remove)
scores_processed = scores.masked_fill(indices_to_remove, self.filter_value)
return scores_processed
| 10,670 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class TopKLogitsWarper(LogitsProcessor):
r"""
[`LogitsProcessor`] that performs top-k, i.e. restricting to the k highest probability elements. Often used
together with [`TemperatureLogitsWarper`] and [`TopPLogitsWarper`].
Args:
top_k (`int`):
The number of highest probability vocabulary tokens to keep for top-k-filtering.
filter_value (`float`, *optional*, defaults to -inf):
All filtered values will be set to this float value.
min_tokens_to_keep (`int`, *optional*, defaults to 1):
Minimum number of tokens that cannot be filtered.
Examples:
```python
>>> from transformers import AutoTokenizer, AutoModelForCausalLM, set_seed
>>> set_seed(1)
>>> model = AutoModelForCausalLM.from_pretrained("distilbert/distilgpt2")
>>> tokenizer = AutoTokenizer.from_pretrained("distilbert/distilgpt2")
>>> inputs = tokenizer("A sequence: A, B, C, D", return_tensors="pt")
| 10,671 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # With sampling, the output is unexpected -- sometimes too unexpected.
>>> outputs = model.generate(**inputs, do_sample=True)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
A sequence: A, B, C, D, E — S — O, P — R
>>> # With `top_k` sampling, the output gets restricted the k most likely tokens.
>>> # Pro tip: In practice, LLMs use `top_k` in the 5-50 range.
>>> outputs = model.generate(**inputs, do_sample=True, top_k=2)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
A sequence: A, B, C, D, E, F, G, H, I
```
"""
def __init__(self, top_k: int, filter_value: float = -float("Inf"), min_tokens_to_keep: int = 1):
if not isinstance(top_k, int) or top_k <= 0:
raise ValueError(f"`top_k` has to be a strictly positive integer, but is {top_k}")
self.top_k = max(top_k, min_tokens_to_keep)
self.filter_value = filter_value
| 10,671 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
top_k = min(self.top_k, scores.size(-1)) # Safety check
# Remove all tokens with a probability less than the last token of the top-k
indices_to_remove = scores < torch.topk(scores, top_k)[0][..., -1, None]
scores_processed = scores.masked_fill(indices_to_remove, self.filter_value)
return scores_processed
| 10,671 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class MinPLogitsWarper(LogitsProcessor):
"""
[`LogitsProcessor`] that performs min-p, i.e. keeps all tokens that are above a minimum probability, scaled by the
probability of the most likely token. As a result, the filter becomes more agressive in the presence of
high-probability tokens, which is a sign of a confident output that we shouldn't deviate from.
Often used together with [`TemperatureLogitsWarper`]. Used as an alternative to [`TopPLogitsWarper`] and
[`TopKLogitsWarper`].
Created by @menhguin and @kalomaze (github handles). Code adapted from [this external PR](https://github.com/oobabooga/text-generation-webui/pull/4449/files)
| 10,672 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
Args:
min_p (`float`):
Minimum token probability, which will be scaled by the probability of the most likely token. It must be a
value between 0 and 1. Typical values are in the 0.01-0.2 range, comparably selective as setting `top_p` in
the 0.99-0.8 range (use the opposite of normal `top_p` values).
filter_value (`float`, *optional*, defaults to -inf):
All filtered values will be set to this float value.
min_tokens_to_keep (`int`, *optional*, defaults to 1):
Minimum number of tokens that cannot be filtered.
Examples:
```python
>>> from transformers import AutoTokenizer, AutoModelForCausalLM, set_seed
>>> set_seed(1)
>>> model = AutoModelForCausalLM.from_pretrained("distilbert/distilgpt2")
>>> tokenizer = AutoTokenizer.from_pretrained("distilbert/distilgpt2")
>>> inputs = tokenizer("A sequence: 1, 2", return_tensors="pt")
| 10,672 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # With sampling, the output is unexpected -- sometimes too unexpected.
>>> outputs = model.generate(**inputs, do_sample=True)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
A sequence: 1, 2, 3 | < 4 (left-hand pointer) ;
<BLANKLINE>
<BLANKLINE>
>>> # With `min_p` sampling, the output gets restricted to high-probability tokens.
>>> # Pro tip: In practice, LLMs use `min_p` in the 0.01-0.2 range.
>>> outputs = model.generate(**inputs, do_sample=True, min_p=0.1)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
A sequence: 1, 2, 3, 4, 5, 6, 7, 8, 9
```
"""
| 10,672 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
def __init__(self, min_p: float, filter_value: float = -float("Inf"), min_tokens_to_keep: int = 1):
if not (0 <= min_p <= 1.0):
raise ValueError(f"`min_p` has to be a float in the [0, 1] interval, but is {min_p}")
if not isinstance(min_tokens_to_keep, int) or (min_tokens_to_keep < 1):
raise ValueError(f"`min_tokens_to_keep` has to be a positive integer, but is {min_tokens_to_keep}")
self.min_p = min_p
self.filter_value = filter_value
self.min_tokens_to_keep = min_tokens_to_keep
| 10,672 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
# Convert logits to probabilities
probs = torch.softmax(scores, dim=-1)
# Get the probability of the top token for each sequence in the batch
top_probs, _ = probs.max(dim=-1, keepdim=True)
# Calculate the actual min_p threshold by scaling min_p with the top token's probability
scaled_min_p = self.min_p * top_probs
# Create a mask for tokens that have a probability less than the scaled min_p
tokens_to_remove = probs < scaled_min_p
sorted_indices = torch.argsort(scores, descending=True, dim=-1)
sorted_indices_to_remove = torch.gather(tokens_to_remove, dim=-1, index=sorted_indices)
# Keep at least min_tokens_to_keep
sorted_indices_to_remove[..., : self.min_tokens_to_keep] = False
| 10,672 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
indices_to_remove = sorted_indices_to_remove.scatter(1, sorted_indices, sorted_indices_to_remove)
scores_processed = scores.masked_fill(indices_to_remove, self.filter_value)
return scores_processed
| 10,672 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class TypicalLogitsWarper(LogitsProcessor):
r"""
[`LogitsProcessor`] that performs typical decoding. Inspired on how humans use language, it prioritizes tokens
whose log probability is close to the entropy of the token probability distribution. This means that the most
likely tokens may be discarded in the process.
See [Typical Decoding for Natural Language Generation](https://arxiv.org/abs/2202.00666) for more information.
Args:
mass (`float`, *optional*, defaults to 0.9):
Value of typical_p between 0 and 1 inclusive, defaults to 0.9.
filter_value (`float`, *optional*, defaults to -inf):
All filtered values will be set to this float value.
min_tokens_to_keep (`int`, *optional*, defaults to 1):
Minimum number of tokens that cannot be filtered.
Examples:
```python
>>> from transformers import AutoTokenizer, AutoModelForCausalLM, set_seed
| 10,673 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> model = AutoModelForCausalLM.from_pretrained("bigscience/bloomz-560m")
>>> tokenizer = AutoTokenizer.from_pretrained("bigscience/bloomz-560m")
>>> inputs = tokenizer("1, 2, 3", return_tensors="pt")
>>> # We can see that greedy decoding produces a sequence of numbers
>>> outputs = model.generate(**inputs)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
>>> # For this particular seed, we can see that sampling produces nearly the same low-information (= low entropy)
>>> # sequence
>>> set_seed(18)
>>> outputs = model.generate(**inputs, do_sample=True)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
1, 2, 3, 4, 5, 6, 7, 8, 9 and 10
| 10,673 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # With `typical_p` set, the most obvious sequence is no longer produced, which may be good for your problem
>>> set_seed(18)
>>> outputs = model.generate(
... **inputs, do_sample=True, typical_p=0.1, return_dict_in_generate=True, output_scores=True
... )
>>> print(tokenizer.batch_decode(outputs.sequences, skip_special_tokens=True)[0])
1, 2, 3 and 5
>>> # We can see that the token corresponding to "4" (token 934) in the second position, the most likely token
>>> # as seen with greedy decoding, was entirely blocked out
>>> print(outputs.scores[1][0, 934])
tensor(-inf)
```
"""
| 10,673 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
def __init__(self, mass: float = 0.9, filter_value: float = -float("Inf"), min_tokens_to_keep: int = 1):
mass = float(mass)
if not (mass > 0 and mass < 1):
raise ValueError(f"`typical_p` has to be a float > 0 and < 1, but is {mass}")
if not isinstance(min_tokens_to_keep, int) or (min_tokens_to_keep < 1):
raise ValueError(f"`min_tokens_to_keep` has to be a positive integer, but is {min_tokens_to_keep}")
self.filter_value = filter_value
self.mass = mass
self.min_tokens_to_keep = min_tokens_to_keep
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
# calculate entropy
normalized = torch.nn.functional.log_softmax(scores, dim=-1)
p = torch.exp(normalized)
ent = -(normalized * p).nansum(-1, keepdim=True)
| 10,673 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
# shift and sort
shifted_scores = torch.abs((-normalized) - ent)
sorted_scores, sorted_indices = torch.sort(shifted_scores, descending=False)
sorted_logits = scores.gather(-1, sorted_indices)
cumulative_probs = sorted_logits.softmax(dim=-1).cumsum(dim=-1)
# Remove tokens with cumulative mass above the threshold
last_ind = (cumulative_probs < self.mass).sum(dim=1)
last_ind.clamp_(max=sorted_scores.shape[-1] - 1)
sorted_indices_to_remove = sorted_scores > sorted_scores.gather(1, last_ind.view(-1, 1))
sorted_indices_to_remove[..., : self.min_tokens_to_keep] = 0
indices_to_remove = sorted_indices_to_remove.scatter(1, sorted_indices, sorted_indices_to_remove)
scores_processed = scores.masked_fill(indices_to_remove, self.filter_value)
return scores_processed
| 10,673 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class EpsilonLogitsWarper(LogitsProcessor):
r"""
[`LogitsProcessor`] that performs epsilon-sampling, i.e. restricting to tokens with `prob >= epsilon`. Takes the
largest min_tokens_to_keep tokens if no tokens satisfy this constraint. See [Truncation Sampling as Language Model
Desmoothing](https://arxiv.org/abs/2210.15191) for more information.
Args:
epsilon (`float`):
If set to > 0, only the most tokens with probabilities `epsilon` or higher are kept for generation.
filter_value (`float`, *optional*, defaults to -inf):
All filtered values will be set to this float value.
min_tokens_to_keep (`int`, *optional*, defaults to 1):
Minimum number of tokens that cannot be filtered.
Examples:
```python
>>> from transformers import AutoTokenizer, AutoModelForCausalLM, set_seed
| 10,674 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> set_seed(1)
>>> model = AutoModelForCausalLM.from_pretrained("distilbert/distilgpt2")
>>> tokenizer = AutoTokenizer.from_pretrained("distilbert/distilgpt2")
>>> inputs = tokenizer("A sequence: 1, 2", return_tensors="pt")
>>> # With sampling, the output is unexpected -- sometimes too unexpected.
>>> outputs = model.generate(**inputs, do_sample=True)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
A sequence: 1, 2, 3 | < 4 (left-hand pointer) ;
<BLANKLINE>
<BLANKLINE>
| 10,674 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # With epsilon sampling, the output gets restricted to high-probability tokens. Note that this is similar to
>>> # Top P sampling, which restricts tokens based on their cumulative probability.
>>> # Pro tip: The paper recomends using `epsilon_cutoff` values between 3e-4 and 9e-4
>>> outputs = model.generate(**inputs, do_sample=True, epsilon_cutoff=0.1)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
A sequence: 1, 2, 3, 4, 5, 6, 7, 8, 9
```
"""
def __init__(self, epsilon: float, filter_value: float = -float("Inf"), min_tokens_to_keep: int = 1):
epsilon = float(epsilon)
if epsilon <= 0 or epsilon >= 1:
raise ValueError(f"`epsilon_cutoff` has to be a float > 0 and < 1, but is {epsilon}")
| 10,674 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
min_tokens_to_keep = int(min_tokens_to_keep)
if min_tokens_to_keep < 1:
raise ValueError(
f"`min_tokens_to_keep` has to be a strictly positive integer, but is {min_tokens_to_keep}"
)
self.epsilon = epsilon
self.filter_value = filter_value
self.min_tokens_to_keep = min_tokens_to_keep
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
# Determine which indices to remove
probabilities = scores.softmax(dim=-1)
indices_to_remove = probabilities < self.epsilon
# Keep the words with the 'min_tokens_to_keep'-highest probabilities
top_k = min(self.min_tokens_to_keep, scores.size(-1)) # Safety check
indices_to_remove = indices_to_remove & (scores < torch.topk(scores, top_k)[0][..., -1, None])
| 10,674 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
scores_processed = scores.masked_fill(indices_to_remove, self.filter_value)
return scores_processed
| 10,674 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class EtaLogitsWarper(LogitsProcessor):
r"""
[`LogitsProcessor`] that performs eta-sampling, a technique to filter out tokens with probabilities below a dynamic
cutoff value, `eta`, which is calculated based on a combination of the hyperparameter `epsilon` and the entropy of
the token probabilities, i.e. `eta := min(epsilon, sqrt(epsilon * e^-entropy(probabilities)))`. Takes the largest
min_tokens_to_keep tokens if no tokens satisfy this constraint. It addresses the issue of poor quality in long
samples of text generated by neural language models leading to more coherent and fluent text. See [Truncation
Sampling as Language Model Desmoothing](https://arxiv.org/abs/2210.15191) for more information. Note: `do_sample`
must be set to `True` for this `LogitsProcessor` to work.
| 10,675 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
Args:
epsilon (`float`):
A float value in the range (0, 1). Hyperparameter used to calculate the dynamic cutoff value, `eta`. The
suggested values from the paper ranges from 3e-4 to 4e-3 depending on the size of the model.
filter_value (`float`, *optional*, defaults to -inf):
All values that are found to be below the dynamic cutoff value, `eta`, are set to this float value. This
parameter is useful when logits need to be modified for very low probability tokens that should be excluded
from generation entirely.
min_tokens_to_keep (`int`, *optional*, defaults to 1):
Specifies the minimum number of tokens that must be kept for generation, regardless of their probabilities.
For example, if `min_tokens_to_keep` is set to 1, at least one token will always be kept for generation,
even if all tokens have probabilities below the cutoff `eta`.
| 10,675 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
device (`str`, *optional*, defaults to `"cpu"`):
The device to allocate the tensors.
| 10,675 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
Examples:
```python
>>> from transformers import AutoTokenizer, AutoModelForCausalLM, set_seed
>>> set_seed(1)
>>> model = AutoModelForCausalLM.from_pretrained("distilbert/distilgpt2")
>>> tokenizer = AutoTokenizer.from_pretrained("distilbert/distilgpt2")
>>> inputs = tokenizer("A sequence: 1, 2", return_tensors="pt")
>>> # With sampling, the output is unexpected -- sometimes too unexpected.
>>> outputs = model.generate(**inputs, do_sample=True)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
A sequence: 1, 2, 3 | < 4 (left-hand pointer) ;
<BLANKLINE>
<BLANKLINE>
| 10,675 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # With eta sampling, the output gets restricted to high-probability tokens. You can see it as a dynamic form of
>>> # epsilon sampling that adapts its cutoff probability based on the entropy (high entropy = lower cutoff).
>>> # Pro tip: The paper recomends using `eta_cutoff` values between 3e-4 to 4e-3
>>> outputs = model.generate(**inputs, do_sample=True, eta_cutoff=0.1)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
A sequence: 1, 2, 3, 4, 5, 6, 7, 8, 9
```
"""
def __init__(
self, epsilon: float, filter_value: float = -float("Inf"), min_tokens_to_keep: int = 1, device: str = "cpu"
):
epsilon = float(epsilon)
if epsilon <= 0 or epsilon >= 1:
raise ValueError(f"`eta_cutoff` has to be a float > 0 and < 1, but is {epsilon}")
| 10,675 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
min_tokens_to_keep = int(min_tokens_to_keep)
if min_tokens_to_keep < 1:
raise ValueError(
f"`min_tokens_to_keep` has to be a strictly positive integer, but is {min_tokens_to_keep}"
)
self.epsilon = torch.tensor(epsilon, device=device)
self.filter_value = filter_value
self.min_tokens_to_keep = min_tokens_to_keep
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
probabilities = scores.softmax(dim=-1)
entropy = torch.distributions.Categorical(logits=scores).entropy()
eta = torch.min(self.epsilon, torch.sqrt(self.epsilon) * torch.exp(-entropy))[..., None]
indices_to_remove = probabilities < eta
| 10,675 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
# Keep the words with the 'min_tokens_to_keep'-highest probabilities
top_k = min(self.min_tokens_to_keep, scores.size(-1)) # Safety check
indices_to_remove = indices_to_remove & (scores < torch.topk(scores, top_k)[0][..., -1, None])
scores_processed = scores.masked_fill(indices_to_remove, self.filter_value)
return scores_processed
| 10,675 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class NoRepeatNGramLogitsProcessor(LogitsProcessor):
r"""
N-grams are groups of "n" consecutive words, characters, or tokens taken from a sequence of text. Given the
sentence: "She runs fast", the bi-grams (n=2) would be ("she", "runs") and ("runs", "fast"). In text generation,
avoiding repetitions of word sequences provides a more diverse output. This [`LogitsProcessor`] enforces no
repetition of n-grams by setting the scores of banned tokens to negative infinity which eliminates those tokens
from consideration when further processing the scores. Note that, for decoder-only models like most LLMs, the
prompt is also considered to obtain the n-grams.
[Fairseq](https://github.com/pytorch/fairseq/blob/a07cb6f40480928c9e0548b737aadd36ee66ac76/fairseq/sequence_generator.py#L345).
<Tip>
| 10,676 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
Use n-gram penalties with care. For instance, penalizing 2-grams (bigrams) in an article about the city of New York
might lead to undesirable outcomes where the city's name appears only once in the entire text.
[Reference](https://huggingface.co/blog/how-to-generate)
</Tip>
Args:
ngram_size (`int`):
All ngrams of size `ngram_size` can only occur once.
Examples:
```py
>>> from transformers import AutoTokenizer, AutoModelForCausalLM
>>> model = AutoModelForCausalLM.from_pretrained("distilbert/distilgpt2")
>>> tokenizer = AutoTokenizer.from_pretrained("distilbert/distilgpt2")
>>> inputs = tokenizer(["Today I"], return_tensors="pt")
>>> output = model.generate(**inputs)
>>> print(tokenizer.decode(output[0], skip_special_tokens=True))
Today I’m not sure if I’m going to be able to do it.
| 10,676 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # Now let's add ngram size using `no_repeat_ngram_size`. This stops the repetitions ("I’m") in the output.
>>> output = model.generate(**inputs, no_repeat_ngram_size=2)
>>> print(tokenizer.decode(output[0], skip_special_tokens=True))
Today I’m not sure if I can get a better understanding of the nature of this issue
```
"""
def __init__(self, ngram_size: int):
if not isinstance(ngram_size, int) or ngram_size <= 0:
raise ValueError(f"`ngram_size` has to be a strictly positive integer, but is {ngram_size}")
self.ngram_size = ngram_size
| 10,676 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
num_batch_hypotheses = scores.shape[0]
cur_len = input_ids.shape[-1]
scores_processed = scores.clone()
banned_batch_tokens = _calc_banned_ngram_tokens(self.ngram_size, input_ids, num_batch_hypotheses, cur_len)
for i, banned_tokens in enumerate(banned_batch_tokens):
scores_processed[i, banned_tokens] = -float("inf")
return scores_processed
| 10,676 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class EncoderNoRepeatNGramLogitsProcessor(LogitsProcessor):
r"""
[`LogitsProcessor`] that works similarly to [`NoRepeatNGramLogitsProcessor`], but applied exclusively to prevent
the repetition of n-grams present in the prompt.
It was designed to promote chattiness in a language model, by preventing the generation of n-grams present in
previous conversation rounds.
Args:
encoder_ngram_size (`int`):
All ngrams of size `ngram_size` can only occur within the encoder input ids.
encoder_input_ids (`int`):
The encoder_input_ids that should not be repeated within the decoder ids.
Examples:
```py
>>> from transformers import AutoTokenizer, AutoModelForCausalLM
>>> model = AutoModelForCausalLM.from_pretrained("bigscience/bloomz-560m")
>>> tokenizer = AutoTokenizer.from_pretrained("bigscience/bloomz-560m")
>>> inputs = tokenizer("Alice: I love cats. What do you love?\nBob:", return_tensors="pt")
| 10,677 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # With greedy decoding, we see Bob repeating Alice's opinion. If Bob was a chatbot, it would be a poor one.
>>> outputs = model.generate(**inputs)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
Alice: I love cats. What do you love?
Bob: I love cats. What do you
>>> # With this logits processor, we can prevent Bob from repeating Alice's opinion.
>>> outputs = model.generate(**inputs, encoder_no_repeat_ngram_size=2)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
Alice: I love cats. What do you love?
Bob: My cats are very cute.
```
"""
| 10,677 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
def __init__(self, encoder_ngram_size: int, encoder_input_ids: torch.LongTensor):
if not isinstance(encoder_ngram_size, int) or encoder_ngram_size <= 0:
raise ValueError(
f"`encoder_ngram_size` has to be a strictly positive integer, but is {encoder_ngram_size}"
)
self.ngram_size = encoder_ngram_size
if len(encoder_input_ids.shape) == 1:
encoder_input_ids = encoder_input_ids.unsqueeze(0)
self.batch_size = encoder_input_ids.shape[0]
self.generated_ngrams = _get_ngrams(encoder_ngram_size, encoder_input_ids, self.batch_size)
| 10,677 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
# B x num_beams
num_hypos = scores.shape[0]
num_beams = num_hypos // self.batch_size
cur_len = input_ids.shape[-1]
scores_processed = scores.clone()
banned_batch_tokens = [
_get_generated_ngrams(
self.generated_ngrams[hypo_idx // num_beams], input_ids[hypo_idx], self.ngram_size, cur_len
)
for hypo_idx in range(num_hypos)
]
for i, banned_tokens in enumerate(banned_batch_tokens):
scores_processed[i, banned_tokens] = -float("inf")
return scores_processed
| 10,677 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class SequenceBiasLogitsProcessor(LogitsProcessor):
"""
[`LogitsProcessor`] that applies an additive bias on sequences. The bias is applied to the last token of a sequence
when the next generated token can complete it. Consequently, to take the most of biasing sequences with more than
one token, consider using beam methods (to gracefully work around partially completed sequences that have a
negative bias) and applying the bias to their prefixes (to ensure the bias is applied earlier).
<Tip>
In order to get the token ids of the sequences that you want to bias, make sure to set `add_prefix_space=True` when
initializing the tokenizer, and use `tokenizer(bad_words, add_special_tokens=False).input_ids`. The
`add_prefix_space` argument is only supported for some slow tokenizers, as fast tokenizers' prefixing behaviours
come from `pre tokenizers`. Read more [here](https://huggingface.co/docs/tokenizers/api/pre-tokenizers).
</Tip>
| 10,678 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
Args:
sequence_bias (`List[List[Union[List[int], float]]]`):
List of lists that maps a sequence of tokens to its bias term (e.g. `[[[10, 45], -2.0],
[[64], -7.5]]`). Positive biases increase the odds of the
sequence being selected, while negative biases do the opposite. If a sequence has a length of 1, its bias
will always be applied. Otherwise, the bias will only be applied if the sequence in question is about to be
completed (in the token selection step after this processor is applied).
Examples:
```python
>>> from transformers import AutoTokenizer, AutoModelForCausalLM
>>> model = AutoModelForCausalLM.from_pretrained("openai-community/gpt2")
>>> tokenizer = AutoTokenizer.from_pretrained("openai-community/gpt2")
>>> inputs = tokenizer(["The full name of Donald is Donald"], return_tensors="pt")
| 10,678 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> summary_ids = model.generate(inputs["input_ids"], max_new_tokens=4)
>>> print(tokenizer.batch_decode(summary_ids, skip_special_tokens=True)[0])
The full name of Donald is Donald J. Trump Jr
>>> # Now let's control generation through a bias. Please note that the tokenizer is initialized differently!
>>> tokenizer_with_prefix_space = AutoTokenizer.from_pretrained("openai-community/gpt2", add_prefix_space=True)
>>> def get_tokens(word):
... return tokenizer_with_prefix_space([word], add_special_tokens=False).input_ids[0]
>>> # If we add a negative bias without beam search, it may become "stuck" in a prefix without good continuations
>>> sequence_bias = [get_tokens("Trump"), -10.0]
>>> biased_ids = model.generate(inputs["input_ids"], max_new_tokens=4, sequence_bias=sequence_bias)
>>> print(tokenizer.batch_decode(biased_ids, skip_special_tokens=True)[0])
The full name of Donald is Donald J. Donald,
| 10,678 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> biased_ids = model.generate(inputs["input_ids"], max_new_tokens=4, num_beams=4, sequence_bias=sequence_bias)
>>> print(tokenizer.batch_decode(biased_ids, skip_special_tokens=True)[0])
The full name of Donald is Donald Rumsfeld,
>>> # We can also add a positive bias to nudge the model towards specific tokens or continuations
>>> sequence_bias = [get_tokens("Donald Duck"), 10.0]
>>> biased_ids = model.generate(inputs["input_ids"], max_new_tokens=4, num_beams=4, sequence_bias=sequence_bias)
>>> print(tokenizer.batch_decode(biased_ids, skip_special_tokens=True)[0])
The full name of Donald is Donald Duck.
```
"""
def __init__(self, sequence_bias: List[List[Union[List[int], float]]]):
self.sequence_bias = sequence_bias
self._validate_arguments()
self._convert_list_arguments_into_dict()
| 10,678 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
# Bias variables that will be populated on the first call (for retrocompatibility purposes, the vocabulary size
# is infered in the first usage, which inhibits initializing here)
self.length_1_bias = None
self.prepared_bias_variables = False
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
# 1 - Prepares the bias tensors. This is only needed the first time the logit processor is called.
if not self.prepared_bias_variables:
self._prepare_bias_variables(scores)
# 2 - prepares an empty bias to add
bias = torch.zeros_like(scores)
# 3 - include the bias from length = 1
bias += self.length_1_bias
| 10,678 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
# 4 - include the bias from length > 1, after determining which biased sequences may be completed.
for sequence_ids, sequence_bias in self.sequence_bias.items():
if len(sequence_ids) == 1: # the sequence is of length 1, already applied
continue
if len(sequence_ids) > input_ids.shape[1]: # the sequence is longer than the context, ignore
continue
prefix_length = len(sequence_ids) - 1
last_token = sequence_ids[-1]
matching_rows = torch.eq(
input_ids[:, -prefix_length:],
torch.tensor(sequence_ids[:-1], dtype=input_ids.dtype, device=input_ids.device),
).prod(dim=1)
bias[:, last_token] += torch.where(
matching_rows.bool(),
torch.tensor(sequence_bias, device=input_ids.device),
torch.tensor(0.0, device=input_ids.device),
)
| 10,678 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
# 5 - apply the bias to the scores
scores_processed = scores + bias
return scores_processed
def _prepare_bias_variables(self, scores: torch.FloatTensor):
vocabulary_size = scores.shape[-1]
# Check biased tokens out of bounds
invalid_biases = []
for sequence_ids in self.sequence_bias:
for token_id in sequence_ids:
if token_id >= vocabulary_size:
invalid_biases.append(token_id)
if len(invalid_biases) > 0:
raise ValueError(
f"The model vocabulary size is {vocabulary_size}, but the following tokens were being biased: "
f"{invalid_biases}"
)
| 10,678 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
# Precompute the bias tensors to be applied. Sequences of length 1 are kept separately, as they can be applied
# with simpler logic.
self.length_1_bias = torch.zeros((vocabulary_size,), dtype=torch.float).to(scores.device)
for sequence_ids, bias in self.sequence_bias.items():
if len(sequence_ids) == 1:
self.length_1_bias[sequence_ids[-1]] = bias
self.prepared_bias_variables = True
| 10,678 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
def _validate_arguments(self):
sequence_bias = self.sequence_bias
if not isinstance(sequence_bias, dict) and not isinstance(sequence_bias, list) or len(sequence_bias) == 0:
raise ValueError(
f"`sequence_bias` has to be a non-empty dictionary, or non-empty list of lists but is {sequence_bias}."
)
if isinstance(sequence_bias, dict) and any(
not isinstance(sequence_ids, tuple) for sequence_ids in sequence_bias.keys()
):
raise ValueError(f"`sequence_bias` has to be a dict with tuples as keys, but is {sequence_bias}.")
if isinstance(sequence_bias, dict) and any(
any((not isinstance(token_id, (int, np.integer)) or token_id < 0) for token_id in sequence_ids)
or len(sequence_ids) == 0
for sequence_ids in sequence_bias.keys()
):
raise ValueError(
f"Each key in `sequence_bias` has to be a non-empty tuple of positive integers, but is "
| 10,678 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
f"{sequence_bias}."
)
| 10,678 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
def all_token_bias_pairs_are_valid(sequence):
return (
isinstance(sequence[0], list)
and all(isinstance(token_id, (int, np.integer)) and token_id > 0 for token_id in sequence[0])
and isinstance(sequence[1], float)
)
if isinstance(sequence_bias, list) and any(
(not all_token_bias_pairs_are_valid(sequence)) or len(sequence) == 0 for sequence in sequence_bias
):
raise ValueError(
f"Each element in `sequence_bias` has to be a non-empty list of lists of positive integers and float, but is "
f"{sequence_bias}."
)
if isinstance(sequence_bias, dict) and any(not isinstance(bias, float) for bias in sequence_bias.values()):
raise ValueError(f"`sequence_bias` has to be a dict with floats as values, but is {sequence_bias}.")
| 10,678 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
def _convert_list_arguments_into_dict(self):
"""BC: we used to accept `dict{tuple of tokens: float}` directly, now we expect a list"""
if isinstance(self.sequence_bias, list):
temp_sequence = self.sequence_bias
self.sequence_bias = {tuple(sublist[0]): sublist[1] for sublist in temp_sequence}
| 10,678 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class NoBadWordsLogitsProcessor(SequenceBiasLogitsProcessor):
"""
[`LogitsProcessor`] that enforces that specified sequences will never be selected.
<Tip>
In order to get the token ids of the words that should not appear in the generated text, make sure to set
`add_prefix_space=True` when initializing the tokenizer, and use `tokenizer(bad_words,
add_special_tokens=False).input_ids`. The `add_prefix_space` argument is only supported for some slow tokenizers,
as fast tokenizers' prefixing behaviours come from `pre tokenizers`. Read more
[here](https://huggingface.co/docs/tokenizers/api/pre-tokenizers).
</Tip>
Args:
bad_words_ids (`List[List[int]]`):
List of list of token ids that are not allowed to be generated.
eos_token_id (`Union[int, List[int], torch.Tensor]`, *optional*):
The id(s) of the *end-of-sequence* token.
Examples:
```python
>>> from transformers import AutoTokenizer, AutoModelForCausalLM
| 10,679 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> model = AutoModelForCausalLM.from_pretrained("openai-community/gpt2")
>>> tokenizer = AutoTokenizer.from_pretrained("openai-community/gpt2")
>>> inputs = tokenizer(["In a word, the cake is a"], return_tensors="pt")
>>> output_ids = model.generate(inputs["input_ids"], max_new_tokens=5, pad_token_id=tokenizer.eos_token_id)
>>> print(tokenizer.batch_decode(output_ids, skip_special_tokens=True)[0])
In a word, the cake is a bit of a mess.
>>> # Now let's take the bad words out. Please note that the tokenizer is initialized differently
>>> tokenizer_with_prefix_space = AutoTokenizer.from_pretrained("openai-community/gpt2", add_prefix_space=True)
| 10,679 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> def get_tokens_as_list(word_list):
... "Converts a sequence of words into a list of tokens"
... tokens_list = []
... for word in word_list:
... tokenized_word = tokenizer_with_prefix_space([word], add_special_tokens=False).input_ids[0]
... tokens_list.append(tokenized_word)
... return tokens_list
>>> bad_words_ids = get_tokens_as_list(word_list=["mess"])
>>> output_ids = model.generate(
... inputs["input_ids"], max_new_tokens=5, bad_words_ids=bad_words_ids, pad_token_id=tokenizer.eos_token_id
... )
>>> print(tokenizer.batch_decode(output_ids, skip_special_tokens=True)[0])
In a word, the cake is a bit of a surprise.
```
"""
def __init__(
self, bad_words_ids: List[List[int]], eos_token_id: Optional[Union[int, List[int], torch.Tensor]] = None
):
self.bad_word_ids = bad_words_ids
self._validate_arguments()
| 10,679 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
# Filter EOS token from bad_words_ids
if eos_token_id is not None:
if not isinstance(eos_token_id, torch.Tensor):
if isinstance(eos_token_id, int):
eos_token_id = [eos_token_id]
eos_token_id = torch.tensor(eos_token_id)
bad_words_ids = list(
filter(lambda bad_token_seq: all(bad_token_seq != [i] for i in eos_token_id), bad_words_ids)
)
# Forbidding a sequence is equivalent to setting its bias to -inf
sequence_bias = {tuple(sequence): float("-inf") for sequence in bad_words_ids}
super().__init__(sequence_bias=sequence_bias)
| 10,679 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
def _validate_arguments(self):
bad_words_ids = self.bad_word_ids
if not isinstance(bad_words_ids, list) or len(bad_words_ids) == 0:
raise ValueError(f"`bad_words_ids` has to be a non-empty list, but is {bad_words_ids}.")
if any(not isinstance(bad_word_ids, list) for bad_word_ids in bad_words_ids):
raise ValueError(f"`bad_words_ids` has to be a list of lists, but is {bad_words_ids}.")
if any(
any((not isinstance(token_id, (int, np.integer)) or token_id < 0) for token_id in bad_word_ids)
for bad_word_ids in bad_words_ids
):
raise ValueError(
f"Each list in `bad_words_ids` has to be a list of positive integers, but is {bad_words_ids}."
)
| 10,679 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class PrefixConstrainedLogitsProcessor(LogitsProcessor):
r"""
[`LogitsProcessor`] that enforces constrained generation and is useful for prefix-conditioned constrained
generation. See [Autoregressive Entity Retrieval](https://arxiv.org/abs/2010.00904) for more information.
Args:
prefix_allowed_tokens_fn (`Callable[[int, torch.Tensor], List[int]]`):
This function constraints the beam search to allowed tokens only at each step. This function takes 2
arguments `inputs_ids` and the batch ID `batch_id`. It has to return a list with the allowed tokens for the
next generation step conditioned on the previously generated tokens `inputs_ids` and the batch ID
`batch_id`.
Examples:
```py
>>> from transformers import AutoTokenizer, AutoModelForCausalLM
>>> model = AutoModelForCausalLM.from_pretrained("bigscience/bloomz-560m")
>>> tokenizer = AutoTokenizer.from_pretrained("bigscience/bloomz-560m")
| 10,680 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> inputs = tokenizer("Alice and Bob", return_tensors="pt")
>>> # By default, it continues generating according to the model's logits
>>> outputs = model.generate(**inputs, max_new_tokens=5)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
Alice and Bob are friends
| 10,680 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # We can contrain it with `prefix_allowed_tokens_fn` to force a certain behavior based on a prefix.
>>> # For instance, we can force an entire entity to be generated when its beginning is detected.
>>> entity = tokenizer(" Bob Marley", return_tensors="pt").input_ids[0] # 3 tokens
>>> def prefix_allowed_tokens_fn(batch_id, input_ids):
... '''
... Attempts to generate 'Bob Marley' when 'Bob' is detected.
... In this case, `batch_id` is not used, but you can set rules for each batch member.
... '''
... if input_ids[-1] == entity[0]:
... return [entity[1].item()]
... elif input_ids[-2] == entity[0] and input_ids[-1] == entity[1]:
... return [entity[2].item()]
... return list(range(tokenizer.vocab_size)) # If no match, allow all tokens
| 10,680 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> outputs = model.generate(**inputs, max_new_tokens=5, prefix_allowed_tokens_fn=prefix_allowed_tokens_fn)
>>> print(tokenizer.batch_decode(outputs, skip_special_tokens=True)[0])
Alice and Bob Marley
```
"""
def __init__(self, prefix_allowed_tokens_fn: Callable[[int, torch.Tensor], List[int]], num_beams: int):
self._prefix_allowed_tokens_fn = prefix_allowed_tokens_fn
self._num_beams = num_beams
| 10,680 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
mask = torch.full_like(scores, -math.inf)
for batch_id, beam_sent in enumerate(input_ids.view(-1, self._num_beams, input_ids.shape[-1])):
for beam_id, sent in enumerate(beam_sent):
prefix_allowed_tokens = self._prefix_allowed_tokens_fn(batch_id, sent)
if len(prefix_allowed_tokens) == 0:
raise ValueError(
f"`prefix_allowed_tokens_fn` returned an empty list for batch ID {batch_id}."
f"This means that the constraint is unsatisfiable. Please check your implementation"
f"of `prefix_allowed_tokens_fn` "
)
mask[batch_id * self._num_beams + beam_id, prefix_allowed_tokens] = 0
scores_processed = scores + mask
return scores_processed
| 10,680 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class HammingDiversityLogitsProcessor(LogitsProcessor):
r"""
[`LogitsProcessor`] that enforces diverse beam search.
Note that this logits processor is only effective for [`PreTrainedModel.group_beam_search`]. See [Diverse Beam
Search: Decoding Diverse Solutions from Neural Sequence Models](https://arxiv.org/pdf/1610.02424.pdf) for more
details.
Traditional beam search often generates very similar sequences across different beams.
`HammingDiversityLogitsProcessor` addresses this by penalizing beams that generate tokens already chosen by other
beams in the same time step.
| 10,681 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
Args:
diversity_penalty (`float`):
This value is subtracted from a beam's score if it generates a token same as any beam from other group at a
particular time. A higher `diversity_penalty` will enforce greater diversity among the beams. Adjusting
this value can help strike a balance between diversity and natural likelihood.
num_beams (`int`):
Number of beams for beam search. 1 means no beam search.
num_beam_groups (`int`):
Number of groups to divide `num_beams` into in order to ensure diversity among different groups of beams.
[this paper](https://arxiv.org/pdf/1610.02424.pdf) for more details.
Examples:
```python
>>> from transformers import AutoTokenizer, AutoModelForSeq2SeqLM
>>> import torch
>>> # Initialize the model and tokenizer
>>> tokenizer = AutoTokenizer.from_pretrained("google-t5/t5-base")
>>> model = AutoModelForSeq2SeqLM.from_pretrained("google-t5/t5-base")
| 10,681 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # A long text about the solar system
>>> text = (
... "The Solar System is a gravitationally bound system comprising the Sun and the objects that orbit it, "
... "either directly or indirectly. Of the objects that orbit the Sun directly, the largest are the eight "
... "planets, with the remainder being smaller objects, such as the five dwarf planets and small Solar System "
... "bodies. The Solar System formed 4.6 billion years ago from the gravitational collapse of a giant "
... "interstellar molecular cloud."
... )
>>> inputs = tokenizer("summarize: " + text, return_tensors="pt")
>>> # Generate diverse summary
>>> outputs_diverse = model.generate(
... **inputs,
... num_beam_groups=2,
... diversity_penalty=10.0,
... max_length=100,
... num_beams=4,
... num_return_sequences=2,
... )
>>> summaries_diverse = tokenizer.batch_decode(outputs_diverse, skip_special_tokens=True)
| 10,681 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # Generate non-diverse summary
>>> outputs_non_diverse = model.generate(
... **inputs,
... max_length=100,
... num_beams=4,
... num_return_sequences=2,
... )
>>> summary_non_diverse = tokenizer.batch_decode(outputs_non_diverse, skip_special_tokens=True)
>>> # With `diversity_penalty`, the resulting beams are much more diverse
>>> print(summary_non_diverse)
['the solar system formed 4.6 billion years ago from the collapse of a giant interstellar molecular cloud. of the objects that orbit the Sun directly, the largest are the eight planets.',
'the Solar System formed 4.6 billion years ago from the collapse of a giant interstellar molecular cloud. of the objects that orbit the Sun directly, the largest are the eight planets.']
| 10,681 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> print(summaries_diverse)
['the solar system formed 4.6 billion years ago from the collapse of a giant interstellar molecular cloud. of the objects that orbit the Sun directly, the largest are the eight planets.',
'the solar system formed 4.6 billion years ago from the collapse of a giant interstellar molecular cloud. of the objects that orbit the Sun directly, the largest are the eight planets. the rest of the objects are smaller objects, such as the five dwarf planets and small solar system bodies.']
```
"""
| 10,681 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
def __init__(self, diversity_penalty: float, num_beams: int, num_beam_groups: int):
if not isinstance(diversity_penalty, float) or (not diversity_penalty > 0.0):
raise ValueError("`diversity_penalty` should be a float strictly larger than 0.")
self._diversity_penalty = diversity_penalty
if not isinstance(num_beams, int) or num_beams < 2:
raise ValueError("`num_beams` should be an integer strictly larger than 1.")
self._num_beams = num_beams
if not isinstance(num_beam_groups, int) or num_beam_groups < 2:
raise ValueError("`num_beam_groups` should be an integer strictly larger than 1.")
if num_beam_groups > num_beams:
raise ValueError("`beam_groups` has to be smaller or equal to `num_beams`.")
self._num_sub_beams = num_beams // num_beam_groups
| 10,681 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
def __call__(
self,
input_ids: torch.LongTensor,
scores: torch.FloatTensor,
current_tokens: torch.LongTensor,
beam_group_idx: int,
) -> torch.FloatTensor:
r"""
Args:
input_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`):
Indices of input sequence tokens in the vocabulary. [What are input IDs?](../glossary#input-ids)
scores (`torch.FloatTensor` of shape `(batch_size, config.vocab_size)`):
Prediction scores of a language modeling head. These can be logits for each vocabulary when not using
beam search or log softmax for each vocabulary token when using beam search
current_tokens (`torch.LongTensor` of shape `(batch_size)`):
Indices of input sequence tokens in the vocabulary, corresponding to the tokens selected by the other
beam groups in the current generation step.
beam_group_idx (`int`):
| 10,681 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
The index of the beam group currently being processed.
| 10,681 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
Return:
`torch.FloatTensor` of shape `(batch_size, config.vocab_size)`:
The processed prediction scores.
"""
# hamming diversity: penalise using same token in current group which was used in previous groups at
# the same time step
batch_size = current_tokens.shape[0] // self._num_beams
group_start_idx = beam_group_idx * self._num_sub_beams
group_end_idx = min(group_start_idx + self._num_sub_beams, self._num_beams)
group_size = group_end_idx - group_start_idx
vocab_size = scores.shape[-1]
if group_start_idx == 0:
return scores
| 10,681 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
scores_processed = scores.clone()
for batch_idx in range(batch_size):
# predicted tokens of last time step of previous groups
previous_group_tokens = current_tokens[
batch_idx * self._num_beams : batch_idx * self._num_beams + group_start_idx
]
token_frequency = torch.bincount(previous_group_tokens, minlength=vocab_size).to(scores.device)
scores_processed[batch_idx * group_size : (batch_idx + 1) * group_size] -= (
self._diversity_penalty * token_frequency
)
return scores_processed
| 10,681 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class ForcedBOSTokenLogitsProcessor(LogitsProcessor):
r"""
[`LogitsProcessor`] that enforces the specified token as the first generated token. Used with encoder-decoder
models.
Args:
bos_token_id (`int`):
The id of the token to force as the first generated token.
Examples:
```python
>>> from transformers import AutoTokenizer, AutoModelForSeq2SeqLM
>>> model = AutoModelForSeq2SeqLM.from_pretrained("google/flan-t5-small")
>>> tokenizer = AutoTokenizer.from_pretrained("google/flan-t5-small")
>>> inputs = tokenizer("Translate from English to German: I love cats.", return_tensors="pt")
>>> # By default, it continues generating according to the model's logits
>>> outputs = model.generate(**inputs, max_new_tokens=10)
>>> print(tokenizer.batch_decode(outputs)[0])
<pad> Ich liebe Kitty.</s>
| 10,682 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # We can use `forced_bos_token_id` to force the start of generation with an encoder-decoder model
>>> # (including forcing it to end straight away with an EOS token)
>>> outputs = model.generate(**inputs, max_new_tokens=10, forced_bos_token_id=tokenizer.eos_token_id)
>>> print(tokenizer.batch_decode(outputs)[0])
<pad></s>
```
"""
def __init__(self, bos_token_id: int):
self.bos_token_id = bos_token_id
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
cur_len = input_ids.shape[-1]
scores_processed = scores
if cur_len == 1:
scores_processed = torch.full_like(scores, -math.inf)
scores_processed[:, self.bos_token_id] = 0
return scores_processed
| 10,682 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class ForcedEOSTokenLogitsProcessor(LogitsProcessor):
r"""
[`LogitsProcessor`] that enforces the specified token as the last generated token when `max_length` is reached.
Args:
max_length (`int`):
The maximum length of the sequence to be generated.
eos_token_id (`Union[int, List[int], torch.Tensor]`):
The id(s) of the *end-of-sequence* token.
device (`str`, *optional*, defaults to `"cpu"`):
The device to allocate the tensors.
Examples:
```python
>>> from transformers import AutoTokenizer, AutoModelForCausalLM
>>> model = AutoModelForCausalLM.from_pretrained("distilbert/distilgpt2")
>>> tokenizer = AutoTokenizer.from_pretrained("distilbert/distilgpt2")
>>> inputs = tokenizer("A sequence: 1, 2, 3", return_tensors="pt")
| 10,683 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # By default, it continues generating according to the model's logits
>>> outputs = model.generate(**inputs, max_new_tokens=10)
>>> print(tokenizer.batch_decode(outputs)[0])
A sequence: 1, 2, 3, 4, 5, 6, 7, 8
>>> # `forced_eos_token_id` ensures the generation ends with a EOS token
>>> outputs = model.generate(**inputs, max_new_tokens=10, forced_eos_token_id=tokenizer.eos_token_id)
>>> print(tokenizer.batch_decode(outputs)[0])
A sequence: 1, 2, 3, 4, 5, 6, 7,<|endoftext|>
```
"""
def __init__(self, max_length: int, eos_token_id: Union[int, List[int], torch.Tensor], device: str = "cpu"):
self.max_length = max_length
if not isinstance(eos_token_id, torch.Tensor):
if isinstance(eos_token_id, int):
eos_token_id = [eos_token_id]
eos_token_id = torch.tensor(eos_token_id, device=device)
self.eos_token_id = eos_token_id
| 10,683 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
if torch.is_floating_point(eos_token_id) or (eos_token_id < 0).any():
raise ValueError(f"`eos_token_id` has to be a list of positive integers, but is {eos_token_id}")
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
cur_len = input_ids.shape[-1]
scores_processed = scores
if cur_len == self.max_length - 1:
scores_processed = torch.full_like(scores, -math.inf)
scores_processed[:, self.eos_token_id] = 0
return scores_processed
| 10,683 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class InfNanRemoveLogitsProcessor(LogitsProcessor):
r"""
[`LogitsProcessor`] that removes all `nan` and `inf` values to avoid the generation method to fail. Note that using
the logits processor should only be used if necessary since it can slow down the generation method.
This logits processor has no `generate` example, as there shouldn't be a correct combination of flags that warrants
its use.
"""
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
# set all nan values to 0.0
scores_processed = torch.where(scores != scores, 0.0, scores)
# set all +/-inf values to max/min possible value
scores_processed = torch.where(scores == float("inf"), torch.finfo(scores.dtype).max, scores_processed)
scores_processed = torch.where(scores == -float("inf"), torch.finfo(scores.dtype).min, scores_processed)
return scores_processed
| 10,684 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class ExponentialDecayLengthPenalty(LogitsProcessor):
r"""
[`LogitsProcessor`] that exponentially increases the score of the `eos_token_id` after `start_index` has been
reached. This allows generating shorter sequences without having a hard cutoff, allowing the `eos_token` to be
predicted in a meaningful position.
Args:
exponential_decay_length_penalty (`tuple(int, float)`):
This tuple shall consist of: `(start_index, decay_factor)` where `start_index` indicates where penalty
starts and `decay_factor` represents the factor of exponential decay
eos_token_id (`Union[int, List[int], torch.Tensor]`):
The id(s) of the *end-of-sequence* token.
input_ids_seq_length (`int`):
The length of the input sequence.
Examples:
```python
>>> from transformers import AutoTokenizer, AutoModelForCausalLM, set_seed
| 10,685 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> model = AutoModelForCausalLM.from_pretrained("openai-community/gpt2")
>>> tokenizer = AutoTokenizer.from_pretrained("openai-community/gpt2")
>>> text = "Just wanted to let you know, I"
>>> inputs = tokenizer(text, return_tensors="pt")
>>> # Let's consider that we want short sentences, so we limit `max_length=30`. However, we observe that the answer
>>> # tends to end abruptly.
>>> set_seed(1)
>>> outputs = model.generate(**inputs, do_sample=True, temperature=0.9, max_length=30, pad_token_id=50256)
>>> print(tokenizer.batch_decode(outputs)[0])
Just wanted to let you know, I received a link to an ebook, the book How To Start A Social Network which was
published in 2010. Although
| 10,685 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # To promote the appearance of the EOS token at the right time, we add the `exponential_decay_length_penalty =
>>> # (start_index, decay_factor)`. Instead of cutting at max_tokens, the output comes to an end before and usually
>>> # with more meaning. What happens is that starting from `start_index` the EOS token score will be increased
>>> # by `decay_factor` exponentially. However, if you set a high decay factor, you may also end up with abruptly
>>> # ending sequences.
>>> set_seed(1)
>>> outputs = model.generate(
... **inputs,
... do_sample=True,
... temperature=0.9,
... max_length=30,
... pad_token_id=50256,
... exponential_decay_length_penalty=(15, 1.6),
... )
>>> print(tokenizer.batch_decode(outputs)[0])
Just wanted to let you know, I received a link to an ebook, the book How To Start A Social Network
which<|endoftext|>
| 10,685 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # With a small decay factor, you will have a higher chance of getting a meaningful sequence.
>>> set_seed(1)
>>> outputs = model.generate(
... **inputs,
... do_sample=True,
... temperature=0.9,
... max_length=30,
... pad_token_id=50256,
... exponential_decay_length_penalty=(15, 1.01),
... )
>>> print(tokenizer.batch_decode(outputs)[0])
Just wanted to let you know, I received a link to an ebook, the book How To Start A Social Network which was
published in 2010.<|endoftext|>
```
"""
def __init__(
self,
exponential_decay_length_penalty: Tuple[int, float],
eos_token_id: Union[int, List[int], torch.Tensor],
input_ids_seq_length: int,
):
self.regulation_start = exponential_decay_length_penalty[0] + input_ids_seq_length
self.regulation_factor = exponential_decay_length_penalty[1]
| 10,685 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
if not isinstance(eos_token_id, torch.Tensor):
if isinstance(eos_token_id, int):
eos_token_id = [eos_token_id]
eos_token_id = torch.tensor(eos_token_id)
self.eos_token_id = eos_token_id
if torch.is_floating_point(eos_token_id) or (eos_token_id < 0).any():
raise ValueError(f"`eos_token_id` has to be a list of positive integers, but is {eos_token_id}")
| 10,685 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
cur_len = input_ids.shape[-1]
self.eos_token_id = self.eos_token_id.to(scores.device)
penalties = torch.zeros_like(scores)
scores_processed = scores
if cur_len > self.regulation_start:
penalty_idx = cur_len - self.regulation_start
# To support negative logits we compute the penalty of the absolute value and add to the original logit
penalty = torch.abs(scores[:, self.eos_token_id]) * (pow(self.regulation_factor, penalty_idx) - 1)
penalties[:, self.eos_token_id] = penalty
scores_processed = scores + penalties
return scores_processed
| 10,685 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class LogitNormalization(LogitsProcessor):
r"""
[`LogitsProcessor`] for normalizing the scores using log-softmax. It's important to normalize
the scores during beam search, after applying the logits processors or warpers, since the search algorithm used in
this library doesn't do it (it only does it before, but they may need re-normalization) but it still supposes that
the scores are normalized when comparing the hypotheses.
Examples:
```python
>>> from transformers import AutoTokenizer, AutoModelForCausalLM
>>> import torch
>>> model = AutoModelForCausalLM.from_pretrained("distilbert/distilgpt2")
>>> tokenizer = AutoTokenizer.from_pretrained("distilbert/distilgpt2")
>>> inputs = tokenizer("A sequence: 1, 2, 3", return_tensors="pt")
| 10,686 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # By default, the scores are not normalized -- the sum of their exponentials is NOT a normalized probability
>>> # distribution, summing to 1
>>> outputs = model.generate(**inputs, return_dict_in_generate=True, output_scores=True)
>>> print(torch.allclose(torch.sum(torch.exp(outputs.scores[-1])), torch.Tensor((1.000,)), rtol=1e-4))
False
>>> # Normalizing them may have a positive impact on beam methods, or when using the scores on your application
>>> outputs = model.generate(**inputs, renormalize_logits=True, return_dict_in_generate=True, output_scores=True)
>>> print(torch.allclose(torch.sum(torch.exp(outputs.scores[-1])), torch.Tensor((1.000,)), rtol=1e-4))
True
```
"""
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
scores_processed = scores.log_softmax(dim=-1)
return scores_processed
| 10,686 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class SuppressTokensAtBeginLogitsProcessor(LogitsProcessor):
r"""
[`SuppressTokensAtBeginLogitsProcessor`] supresses a list of tokens as soon as the `generate` function starts
generating using `begin_index` tokens. This should ensure that the tokens defined by `begin_suppress_tokens` are
not generated at the beginning. Originally created for
[Whisper](https://huggingface.co/docs/transformers/model_doc/whisper).
Examples:
```python
>>> from transformers import AutoProcessor, WhisperForConditionalGeneration
>>> from datasets import load_dataset
>>> processor = AutoProcessor.from_pretrained("openai/whisper-tiny.en")
>>> model = WhisperForConditionalGeneration.from_pretrained("openai/whisper-tiny.en")
>>> ds = load_dataset("hf-internal-testing/librispeech_asr_dummy", "clean", split="validation")
>>> inputs = processor(ds[0]["audio"]["array"], return_tensors="pt")
| 10,687 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # Whisper has `begin_suppress_tokens` set by default (= `[220, 50256]`). 50256 is the EOS token, so this means
>>> # it can't generate and EOS token in the first iteration, but it can in the others.
>>> outputs = model.generate(**inputs, return_dict_in_generate=True, output_scores=True)
>>> print(outputs.scores[0][0, 50256])
tensor(-inf)
>>> print(outputs.scores[-1][0, 50256]) # in other places we can see some probability mass for EOS
tensor(29.9010)
>>> # If we disable `begin_suppress_tokens`, we can generate EOS in the first iteration.
>>> outputs = model.generate(
... **inputs, return_dict_in_generate=True, output_scores=True, begin_suppress_tokens=None
... )
>>> print(outputs.scores[0][0, 50256])
tensor(11.2027)
```
"""
def __init__(self, begin_suppress_tokens, begin_index, device: str = "cpu"):
self.begin_suppress_tokens = torch.tensor(list(begin_suppress_tokens), device=device)
self.begin_index = begin_index
| 10,687 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
def set_begin_index(self, begin_index):
self.begin_index = begin_index
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
vocab_tensor = torch.arange(scores.shape[-1], device=scores.device)
suppress_token_mask = isin_mps_friendly(vocab_tensor, self.begin_suppress_tokens)
scores_processed = scores
if input_ids.shape[-1] == self.begin_index:
scores_processed = torch.where(suppress_token_mask, -float("inf"), scores)
return scores_processed
| 10,687 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class SuppressTokensLogitsProcessor(LogitsProcessor):
r"""
This processor can be used to suppress a list of tokens. The processor will set their log probs to `-inf` so
that they are not generated. Originally created for
[Whisper](https://huggingface.co/docs/transformers/model_doc/whisper).
Examples:
```python
>>> from transformers import AutoProcessor, WhisperForConditionalGeneration
>>> from datasets import load_dataset
>>> processor = AutoProcessor.from_pretrained("openai/whisper-tiny.en")
>>> model = WhisperForConditionalGeneration.from_pretrained("openai/whisper-tiny.en")
>>> ds = load_dataset("hf-internal-testing/librispeech_asr_dummy", "clean", split="validation")
>>> inputs = processor(ds[0]["audio"]["array"], return_tensors="pt")
| 10,688 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
>>> # Whisper has a long list of suppressed tokens. For instance, in this case, the token 1 is suppressed by default.
>>> outputs = model.generate(**inputs, return_dict_in_generate=True, output_scores=True)
>>> print(outputs.scores[1][0, 1]) # 1 (and not 0) is the first freely generated token
tensor(-inf)
>>> # If we disable `suppress_tokens`, we can generate it.
>>> outputs = model.generate(**inputs, return_dict_in_generate=True, output_scores=True, suppress_tokens=None)
>>> print(outputs.scores[1][0, 1])
tensor(6.0678)
```
"""
def __init__(self, suppress_tokens, device: str = "cpu"):
self.suppress_tokens = torch.tensor(list(suppress_tokens), device=device)
| 10,688 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
@add_start_docstrings(LOGITS_PROCESSOR_INPUTS_DOCSTRING)
def __call__(self, input_ids: torch.LongTensor, scores: torch.FloatTensor) -> torch.FloatTensor:
vocab_tensor = torch.arange(scores.shape[-1], device=scores.device)
suppress_token_mask = isin_mps_friendly(vocab_tensor, self.suppress_tokens)
scores = torch.where(suppress_token_mask, -float("inf"), scores)
return scores
| 10,688 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
class WhisperTimeStampLogitsProcessor(LogitsProcessor):
r"""
[`LogitsProcessor`] that modifies the logits for the generation of timestamps in the transcription. When the input
tokens are at a specific threshold, the processor sets the scores to negative infinity. The processor makes sure
that timestamp tokens appear in pairs, by masking out the logits that would break this pairing pattern. This is
done to maintain the consistency and structure of generated timestamps. It also ensures that when the predicted
probability of sampling any of the timestamp token is greater than any individual non-timestamp token, those
non-timestamp logits are set to negative infinity. This is done to ensure the generation of timestamps over other
potential tokens.
See [the paper](https://arxiv.org/abs/2212.04356) for more information.
| 10,689 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
Args:
generate_config (`GenerateConfig`):
The generate config used to generate the output. The following parameters are required:
eos_token_id (`int`, *optional*, defaults to 50257):
The id of the *end-of-sequence* token.
no_timestamps_token_id (`int`, *optional*, defaults to 50363):
The id of the `"<|notimestamps|>"` token.
max_initial_timestamp_index (`int`, *optional*, defaults to 1):
Used to set the maximum value of the initial timestamp. This is used to prevent the model from
predicting timestamps that are too far in the future.
begin_index (`Optional`, *optional*): Token index of the first token that is generated by the model.
_detect_timestamp_from_logprob (`bool`, *optional*): Whether timestamps can be predicted from logprobs over all timestamps.
| 10,689 |
/Users/nielsrogge/Documents/python_projecten/transformers/src/transformers/generation/logits_process.py
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.