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#!/usr/bin/env python
# coding: utf-8
# In[1]:
import pickle
import copy
import numpy as np
import pickle
#pip install torch
import torch
import torch.nn as nn
#pip install transformers
from transformers import BertModel, BertTokenizer
#import utils
# In[2]:
#!pip install nltk
#!pip install tensorflow --upgrade
import os
import torch
import torch.nn as nn
import transformers
from transformers import BertModel, BertTokenizer
# from torch_shallow_neural_classifier import TorchShallowNeuralClassifier
# from torch_rnn_classifier import TorchRNNModel
# from torch_rnn_classifier import TorchRNNClassifier
# from torch_rnn_classifier import TorchRNNClassifierModel
# from torch_rnn_classifier import TorchRNNClassifier
# import sst
# import utils
#!pip install numpy --upgrade
import numpy as np
import pandas as pd
#pip install nltk
from nltk.tokenize.treebank import TreebankWordDetokenizer
from nltk.tokenize.treebank import TreebankWordTokenizer
import tensorflow as tf
# In[79]:
class TorchModelBase:
def __init__(self,
batch_size=1028,
max_iter=1000,
eta=0.001,
optimizer_class=torch.optim.Adam,
l2_strength=0,
gradient_accumulation_steps=1,
max_grad_norm=None,
warm_start=False,
early_stopping=False,
validation_fraction=0.1,
shuffle_train=True,
n_iter_no_change=10,
tol=1e-5,
device=None,
display_progress=True,
**optimizer_kwargs):
"""
Base class for all the PyTorch-based models.
Parameters
----------
batch_size: int
Number of examples per batch. Batching is handled by a
`torch.utils.data.DataLoader`. Final batches can have fewer
examples, depending on the total number of examples in the
dataset.
max_iter: int
Maximum number of training iterations. This will interact
with `early_stopping`, `n_iter_no_change`, and `tol` in the
sense that this limit will be reached if and only if and
conditions triggered by those other parameters are not met.
eta : float
Learning rate for the optimizer.
optimizer_class: `torch.optimizer.Optimizer`
Any PyTorch optimizer should work. Additional arguments
can be passed to this object via `**optimizer_kwargs`. The
optimizer itself is built by `self.build_optimizer` when
`fit` is called.
l2_strength: float
L2 regularization parameters for the optimizer. The default
of 0 means no regularization, and larger values correspond
to stronger regularization.
gradient_accumulation_steps: int
Controls how often the model parameters are updated during
learning. For example, with `gradient_accumulation_steps=2`,
the parameters are updated after every other batch. The primary
use case for `gradient_accumulation_steps > 1` is where the
model is very large, so only small batches of examples can be
fit into memory. The updates based on these small batches can
have high variance, so accumulating a few batches before
updating can smooth the process out.
max_grad_norm: None or float
If not `None`, then `torch.nn.utils.clip_grad_norm_` is used
to clip all the model parameters to within the range set
by this value. This is a kind of brute-force way of keeping
the parameter values from growing absurdly large or small.
warm_start: bool
If `False`, then repeated calls to `fit` will reset all the
optimization settings: the model parameters, the optimizer,
and the metadata we collect during optimization. If `True`,
then calling `fit` twice with `max_iter=N` should be the same
as calling fit once with `max_iter=N*2`.
early_stopping: bool
If `True`, then `validation_fraction` of the data given to
`fit` are held out and used to assess the model after every
epoch. The best scoring model is stored in an attribute
`best_parameters`. If an improvement of at least `self.tol`
isn't seen after `n_iter_no_change` iterations, then training
stops and `self.model` is set to use `best_parameters`.
validation_fraction: float
Percentage of the data given to `fit` to hold out for use in
early stopping. Ignored if `early_stopping=False`
shuffle_train: bool
Whether to shuffle the training data.
n_iter_no_change: int
Number of epochs used to control convergence and early
stopping. Where `early_stopping=True`, training stops if an
improvement of more than `self.tol` isn't seen after this
many epochs. If `early_stopping=False`, then training stops
if the epoch error doesn't drop by at least `self.tol` after
this many epochs.
tol: float
Value used to control `early_stopping` and convergence.
device: str or None
Used to set the device on which the PyTorch computations will
be done. If `device=None`, this will choose a CUDA device if
one is available, else the CPU is used.
display_progress: bool
Whether to print optimization information incrementally to
`sys.stderr` during training.
**optimizer_kwargs: kwargs
Any additional keywords given to the model will be passed to
the optimizer -- see `self.build_optimizer`. The intent is to
make it easy to tune these as hyperparameters will still
allowing the user to specify just `optimizer_class` rather
than setting up a full optimizer.
Attributes
----------
params: list
All the keyword arguments are parameters and, with the
exception of `display_progress`, their names are added to
this list to support working with them using tools from
`sklearn.model_selection`.
"""
self.batch_size = batch_size
self.max_iter = max_iter
self.eta = eta
self.optimizer_class = optimizer_class
self.l2_strength = l2_strength
self.gradient_accumulation_steps = max([gradient_accumulation_steps, 1])
self.max_grad_norm = max_grad_norm
self.warm_start = warm_start
self.early_stopping = early_stopping
self.validation_fraction = validation_fraction
self.shuffle_train = shuffle_train
self.n_iter_no_change = n_iter_no_change
self.tol = tol
if device is None:
device = "cuda" if torch.cuda.is_available() else "cpu"
self.device = torch.device(device)
self.display_progress = display_progress
self.optimizer_kwargs = optimizer_kwargs
for k, v in self.optimizer_kwargs.items():
setattr(self, k, v)
self.params = [
'batch_size',
'max_iter',
'eta',
'optimizer_class',
'l2_strength',
'gradient_accumulation_steps',
'max_grad_norm',
'validation_fraction',
'early_stopping',
'n_iter_no_change',
'warm_start',
'tol']
self.params += list(optimizer_kwargs.keys())
def build_dataset(self, *args, **kwargs):
"""
Subclasses are required to define this method. Perhaps the most
important design note is that the function should be prepared to
return datasets that are appropriate for both training and
prediction. For training, we expect `*args` to have labels in
final position. For prediction, we expect all of `*args` to be
model inputs. For example, in a simple classifier, we expect
`*args` to be a pair `(X, y)` for training and so this method
should return something like:
`torch.utils.data.TensorDataset(X, y)`
For prediction, we get only `X`, so we should return
`torch.utils.data.TensorDataset(X)`
Parameters
----------
*args: any arguments to be used to create the dataset
**kwargs: any desired keyword arguments
Returns
-------
`torch.utils.data.Dataset` or a custom subclass thereof
"""
raise NotImplementedError
def build_graph(self, *args, **kwargs):
"""
Build the core computational graph. This is called only after
`fit` is called. The return value of this function becomes the
the `self.model` attribute.
Parameters
----------
*args: any arguments to be used to create the dataset
**kwargs: any desired keyword arguments
Returns
-------
nn.Module or subclass thereof
"""
raise NotImplementedError
def score(self, *args):
"""
Required by the `sklearn.model_selection` tools. This function
needs to take the same arguments as `fit`. For `*args` is usually
an `(X, y)` pair of features and labels, and `self.predict(X)`
is called and then some kind of scoring function is used to
compare those predictions with `y`. The return value should be
some kind of appropriate score for the model in question.
Notes
-----
For early stopping, we use this function to get scores and
assume that larger scores are better. This would conflict with
using, say, a mean-squared-error scoring function.
"""
raise NotImplementedError
def build_optimizer(self):
"""
Builds the optimizer. This function is called only when `fit`
is called.
Returns
-------
torch.optimizer.Optimizer
"""
return self.optimizer_class(
self.model.parameters(),
lr=self.eta,
weight_decay=self.l2_strength,
**self.optimizer_kwargs)
def fit(self, *args):
"""
Generic optimization method.
Parameters
----------
*args: list of objects
We assume that the final element of args give the labels
and all the preceding elements give the system inputs.
For regular supervised learning, this is like (X, y), but
we allow for models that might use multiple data structures
for their inputs.
Attributes
----------
model: nn.Module or subclass thereof
Set by `build_graph`. If `warm_start=True`, then this is
initialized only by the first call to `fit`.
optimizer: torch.optimizer.Optimizer
Set by `build_optimizer`. If `warm_start=True`, then this is
initialized only by the first call to `fit`.
errors: list of float
List of errors. If `warm_start=True`, then this is
initialized only by the first call to `fit`. Thus, where
`max_iter=5`, if we call `fit` twice with `warm_start=True`,
then `errors` will end up with 10 floats in it.
validation_scores: list
List of scores. This is filled only if `early_stopping=True`.
If `warm_start=True`, then this is initialized only by the
first call to `fit`. Thus, where `max_iter=5`, if we call
`fit` twice with `warm_start=True`, then `validation_scores`
will end up with 10 floats in it.
no_improvement_count: int
Used to control early stopping and convergence. These values
are controlled by `_update_no_improvement_count_early_stopping`
or `_update_no_improvement_count_errors`. If `warm_start=True`,
then this is initialized only by the first call to `fit`. Thus,
in that situation, the values could accumulate across calls to
`fit`.
best_error: float
Used to control convergence. Smaller is assumed to be better.
If `warm_start=True`, then this is initialized only by the first
call to `fit`. It will be reset by
`_update_no_improvement_count_errors` depending on how the
optimization is proceeding.
best_score: float
Used to control early stopping. If `warm_start=True`, then this
is initialized only by the first call to `fit`. It will be reset
by `_update_no_improvement_count_early_stopping` depending on how
the optimization is proceeding. Important: we currently assume
that larger scores are better. As a result, we will not get the
correct results for, e.g., a scoring function based in
`mean_squared_error`. See `self.score` for additional details.
best_parameters: dict
This is a PyTorch state dict. It is used if and only if
`early_stopping=True`. In that case, it is updated whenever
`best_score` is improved numerically. If the early stopping
criteria are met, then `self.model` is reset to contain these
parameters before `fit` exits.
Returns
-------
self
"""
if self.early_stopping:
args, dev = self._build_validation_split(
*args, validation_fraction=self.validation_fraction)
# Dataset:
dataset = self.build_dataset(*args)
dataloader = self._build_dataloader(dataset, shuffle=self.shuffle_train)
# Set up parameters needed to use the model. This is a separate
# function to support using pretrained models for prediction,
# where it might not be desirable to call `fit`.
self.initialize()
# Make sure the model is where we want it:
self.model.to(self.device)
self.model.train()
self.optimizer.zero_grad()
for iteration in range(1, self.max_iter+1):
epoch_error = 0.0
for batch_num, batch in enumerate(dataloader, start=1):
batch = [x.to(self.device, non_blocking=True) for x in batch]
X_batch = batch[: -1]
y_batch = batch[-1]
batch_preds = self.model(*X_batch)
err = self.loss(batch_preds, y_batch)
if self.gradient_accumulation_steps > 1 and \
self.loss.reduction == "mean":
err /= self.gradient_accumulation_steps
err.backward()
epoch_error += err.item()
if batch_num % self.gradient_accumulation_steps == 0 or \
batch_num == len(dataloader):
if self.max_grad_norm is not None:
torch.nn.utils.clip_grad_norm_(
self.model.parameters(), self.max_grad_norm)
self.optimizer.step()
self.optimizer.zero_grad()
# Stopping criteria:
if self.early_stopping:
self._update_no_improvement_count_early_stopping(*dev)
if self.no_improvement_count > self.n_iter_no_change:
utils.progress_bar(
"Stopping after epoch {}. Validation score did "
"not improve by tol={} for more than {} epochs. "
"Final error is {}".format(iteration, self.tol,
self.n_iter_no_change, epoch_error),
verbose=self.display_progress)
break
else:
self._update_no_improvement_count_errors(epoch_error)
if self.no_improvement_count > self.n_iter_no_change:
utils.progress_bar(
"Stopping after epoch {}. Training loss did "
"not improve more than tol={}. Final error "
"is {}.".format(iteration, self.tol, epoch_error),
verbose=self.display_progress)
break
utils.progress_bar(
"Finished epoch {} of {}; error is {}".format(
iteration, self.max_iter, epoch_error),
verbose=self.display_progress)
if self.early_stopping:
self.model.load_state_dict(self.best_parameters)
return self
def initialize(self):
"""
Method called by `fit` to establish core attributes. To use a
pretrained model without calling `fit`, one can use this
method.
"""
if not self.warm_start or not hasattr(self, "model"):
self.model = self.build_graph()
# This device move has to happen before the optimizer is built:
# https://pytorch.org/docs/master/optim.html#constructing-it
self.model.to(self.device)
self.optimizer = self.build_optimizer()
self.errors = []
self.validation_scores = []
self.no_improvement_count = 0
self.best_error = np.inf
self.best_score = -np.inf
self.best_parameters = None
@staticmethod
def _build_validation_split(*args, validation_fraction=0.2):
"""
Split `*args` into train and dev portions for early stopping.
We use `train_test_split`. For args of length N, then delivers
N*2 objects, arranged as
X1_train, X1_test, X2_train, X2_test, ..., y_train, y_test
Parameters
----------
*args: List of objects to split.
validation_fraction: float
Percentage of the examples to use for the dev portion. In
`fit`, this is determined by `self.validation_fraction`.
We give it as an argument here to facilitate unit testing.
Returns
-------
Pair of tuples `train` and `dev`
"""
if validation_fraction == 1.0:
return args, args
results = train_test_split(*args, test_size=validation_fraction)
train = results[::2]
dev = results[1::2]
return train, dev
def _build_dataloader(self, dataset, shuffle=True):
"""
Internal method used to create a dataloader from a dataset.
This is used by `fit` and `_predict`.
Parameters
----------
dataset: torch.utils.data.Dataset
shuffle: bool
When training, this is `True`. For prediction, this is
crucially set to `False` so that the examples are not
shuffled out of order with respect to labels that might
be used for assessment.
Returns
-------
torch.utils.data.DataLoader
"""
if hasattr(dataset, "collate_fn"):
collate_fn = dataset.collate_fn
else:
collate_fn = None
dataloader = torch.utils.data.DataLoader(
dataset,
batch_size=self.batch_size,
shuffle=shuffle,
pin_memory=True,
collate_fn=collate_fn)
return dataloader
def _update_no_improvement_count_early_stopping(self, *dev):
"""
Internal method used by `fit` to control early stopping.
The method uses `self.score(*dev)` for scoring and updates
`self.validation_scores`, `self.no_improvement_count`,
`self.best_score`, `self.best_parameters` as appropriate.
"""
score = self.score(*dev)
self.validation_scores.append(score)
# If the score isn't at least `self.tol` better, increment:
if score < (self.best_score + self.tol):
self.no_improvement_count += 1
else:
self.no_improvement_count = 0
# If the current score is numerically better than all previous
# scores, update the best parameters:
if score > self.best_score:
self.best_parameters = copy.deepcopy(self.model.state_dict())
self.best_score = score
self.model.train()
def _update_no_improvement_count_errors(self, epoch_error):
"""
Internal method used by `fit` to control convergence.
The method uses `epoch_error`, `self.best_error`, and
`self.tol` to make decisions, and it updates `self.errors`,
`self.no_improvement_count`, and `self.best_error` as
appropriate.
"""
if epoch_error > (self.best_error - self.tol):
self.no_improvement_count += 1
else:
self.no_improvement_count = 0
if epoch_error < self.best_error:
self.best_error = epoch_error
self.errors.append(epoch_error)
def _predict(self, *args, device=None):
"""
Internal method that subclasses are expected to use to define
their own `predict` functions. The hope is that this method
can do all the data organization and other details, allowing
subclasses to have compact predict methods that just encode
the core logic specific to them.
Parameters
----------
*args: system inputs
device: str or None
Allows the user to temporarily change the device used
during prediction. This is useful if predictions require a
lot of memory and so are better done on the CPU. After
prediction is done, the model is returned to `self.device`.
Returns
-------
The precise return value depends on the nature of the predictions.
If the predictions have the same shape across all batches, then
we return a single tensor concatenation of them. If the shape
can vary across batches, as is common for sequence prediction,
then we return a list of tensors of varying length.
"""
device = self.device if device is None else torch.device(device)
# Dataset:
dataset = self.build_dataset(*args)
dataloader = self._build_dataloader(dataset, shuffle=False)
# Model:
self.model.to(device)
self.model.eval()
preds = []
with torch.no_grad():
for batch in dataloader:
X = [x.to(device, non_blocking=True) for x in batch]
preds.append(self.model(*X))
# Make sure the model is back on the instance device:
#self.model.to(self.device)
# If the batch outputs differ only in their batch size, sharing
# all other dimensions, then we can concatenate them and maintain
# a tensor. For simple classification problems, this should hold.
if all(x.shape[1: ] == preds[0].shape[1: ] for x in preds[1: ]):
return torch.cat(preds, axis=0)
# The batch outputs might differ along other dimensions. This is
# common for sequence prediction, where different batches might
# have different max lengths, since we pad on a per-batch basis.
# In this case, we can't concatenate them, so we return a list
# of the predictions, where each prediction is a tensor. Note:
# the predictions might still be padded and so need trimming on a
# per example basis.
else:
return [p for batch in preds for p in batch]
def get_params(self, deep=True):
params = self.params.copy()
# Obligatorily add `vocab` so that sklearn passes it in when
# creating new model instances during cross-validation:
if hasattr(self, 'vocab'):
params += ['vocab']
return {p: getattr(self, p) for p in params}
def set_params(self, **params):
for key, val in params.items():
if key not in self.params:
raise ValueError(
"{} is not a parameter for {}. For the list of "
"available parameters, use `self.params`.".format(
key, self.__class__.__name__))
else:
setattr(self, key, val)
return self
def to_pickle(self, output_filename):
"""
Serialize the entire class instance. Importantly, this is
different from using the standard `torch.save` method:
torch.save(self.model.state_dict(), output_filename)
The above stores only the underlying model parameters. In
contrast, the current method ensures that all of the model
parameters are on the CPU and then stores the full instance.
This is necessary to ensure that we retain all the information
needed to read new examples, do additional training, make
predictions, and so forth.
Parameters
----------
output_filename : str
Full path for the output file.
"""
self.model = self.model.cpu()
with open(output_filename, 'wb') as f:
pickle.dump(self, f)
@staticmethod
def from_pickle(src_filename):
"""
Load an entire class instance onto the CPU. This also sets
`self.warm_start=True` so that the loaded parameters are used
if `fit` is called.
Importantly, this is different from recommended PyTorch method:
self.model.load_state_dict(torch.load(src_filename))
We cannot reliably do this with new instances, because we need
to see new examples in order to set some of the model
dimensionalities and obtain information about what the class
labels are. Thus, the current method loads an entire serialized
class as created by `to_pickle`.
The training and prediction code move the model parameters to
`self.device`.
Parameters
----------
src_filename : str
Full path to the serialized model file.
"""
with open(src_filename, 'rb') as f:
return pickle.load(f)
def __repr__(self):
param_str = ["{}={}".format(a, getattr(self, a)) for a in self.params]
param_str = ",\n\t".join(param_str)
return "{}(\n\t{})".format(self.__class__.__name__, param_str)
# In[80]:
class TorchShallowNeuralClassifier(TorchModelBase):
def __init__(self,
hidden_dim=50,
hidden_activation=nn.Tanh(),
**base_kwargs):
"""
A model
h = f(xW_xh + b_h)
y = softmax(hW_hy + b_y)
with a cross-entropy loss and f determined by `hidden_activation`.
Parameters
----------
hidden_dim : int
Dimensionality of the hidden layer.
hidden_activation : nn.Module
The non-activation function used by the network for the
hidden layer.
**base_kwargs
For details, see `torch_model_base.py`.
Attributes
----------
loss: nn.CrossEntropyLoss(reduction="mean")
self.params: list
Extends TorchModelBase.params with names for all of the
arguments for this class to support tuning of these values
using `sklearn.model_selection` tools.
"""
self.hidden_dim = hidden_dim
self.hidden_activation = hidden_activation
super().__init__(**base_kwargs)
self.loss = nn.CrossEntropyLoss(reduction="mean")
self.params += ['hidden_dim', 'hidden_activation']
def build_graph(self):
"""
Define the model's computation graph.
Returns
-------
nn.Module
"""
return nn.Sequential(
nn.Linear(self.input_dim, self.hidden_dim),
self.hidden_activation,
nn.Linear(self.hidden_dim, self.n_classes_))
def build_dataset(self, X, y=None):
"""
Define datasets for the model.
Parameters
----------
X : iterable of length `n_examples`
Each element must have the same length.
y: None or iterable of length `n_examples`
Attributes
----------
input_dim : int
Set based on `X.shape[1]` after `X` has been converted to
`np.array`.
Returns
-------
torch.utils.data.TensorDataset` Where `y=None`, the dataset will
yield single tensors `X`. Where `y` is specified, it will yield
`(X, y)` pairs.
"""
X = np.array(X)
self.input_dim = X.shape[1]
X = torch.FloatTensor(X)
if y is None:
dataset = torch.utils.data.TensorDataset(X)
else:
self.classes_ = sorted(set(y))
self.n_classes_ = len(self.classes_)
class2index = dict(zip(self.classes_, range(self.n_classes_)))
y = [class2index[label] for label in y]
y = torch.tensor(y)
dataset = torch.utils.data.TensorDataset(X, y)
return dataset
def score(self, X, y, device=None):
"""
Uses macro-F1 as the score function. Note: this departs from
`sklearn`, where classifiers use accuracy as their scoring
function. Using macro-F1 is more consistent with our course.
This function can be used to evaluate models, but its primary
use is in cross-validation and hyperparameter tuning.
Parameters
----------
X: np.array, shape `(n_examples, n_features)`
y: iterable, shape `len(n_examples)`
These can be the raw labels. They will converted internally
as needed. See `build_dataset`.
device: str or None
Allows the user to temporarily change the device used
during prediction. This is useful if predictions require a
lot of memory and so are better done on the CPU. After
prediction is done, the model is returned to `self.device`.
Returns
-------
float
"""
preds = self.predict(X, device=device)
return utils.safe_macro_f1(y, preds)
def predict_proba(self, X, device=None):
"""
Predicted probabilities for the examples in `X`.
Parameters
----------
X : np.array, shape `(n_examples, n_features)`
device: str or None
Allows the user to temporarily change the device used
during prediction. This is useful if predictions require a
lot of memory and so are better done on the CPU. After
prediction is done, the model is returned to `self.device`.
Returns
-------
np.array, shape `(len(X), self.n_classes_)`
Each row of this matrix will sum to 1.0.
"""
#print(device)
preds = self._predict(X, device=device)
probs = torch.softmax(preds, dim=1).cpu().numpy()
return probs
def predict(self, X, device="cpu"):
"""
Predicted labels for the examples in `X`. These are converted
from the integers that PyTorch needs back to their original
values in `self.classes_`.
Parameters
----------
X : np.array, shape `(n_examples, n_features)`
device: str or None
Allows the user to temporarily change the device used
during prediction. This is useful if predictions require a
lot of memory and so are better done on the CPU. After
prediction is done, the model is returned to `self.device`.
Returns
-------
list, length len(X)
"""
#print(device)
probs = self.predict_proba(X, device=device)
#return [{self.classes_[i.argmax(axis=1):] for i in probs]
return [{self.classes_[i]:j} for i,j in zip(probs.argmax(axis=1),probs.max(axis=1))]
# In[81]:
class HfBertClassifierModel1(nn.Module):
def __init__(self, n_classes, weights_name='bert-base-cased',hidden_dim=64):
super().__init__()
self.n_classes = n_classes
self.weights_name = weights_name
self.hidden_dim = hidden_dim
self.bert = BertModel.from_pretrained(self.weights_name)
self.bert.train()
self.input_dim = self.bert.embeddings.word_embeddings.embedding_dim
# The only new parameters -- the classifier:
self.classifier_layer = nn.Sequential(
nn.Linear(self.input_dim, self.hidden_dim),
nn.ReLU(),
nn.Dropout(0.1),
nn.Linear(self.hidden_dim, self.n_classes))
def forward(self, indices, mask):
reps = self.bert(
indices, attention_mask=mask)
return self.classifier_layer(reps.pooler_output)
# In[82]:
class HfBertClassifier_all(TorchShallowNeuralClassifier):
def __init__(self, weights_name, *args, **kwargs):
self.weights_name = weights_name
self.tokenizer = BertTokenizer.from_pretrained(self.weights_name)
#self.hidden_dim=kwargs['hidden_dim']
super().__init__(*args, **kwargs)
self.params += ['weights_name']
def build_graph(self):
return HfBertClassifierModel1(self.n_classes_, self.weights_name)
def build_dataset(self, X, y=None):
data = self.tokenizer.batch_encode_plus(
X,
max_length=512,
add_special_tokens=True,
padding='longest',
truncation=True,
return_attention_mask=True)
indices = torch.tensor(data['input_ids'])
mask = torch.tensor(data['attention_mask'])
if y is None:
dataset = torch.utils.data.TensorDataset(indices, mask)
else:
self.classes_ = sorted(set(y))
self.n_classes_ = len(self.classes_)
class2index = dict(zip(self.classes_, range(self.n_classes_)))
y = [class2index[label] for label in y]
y = torch.tensor(y)
dataset = torch.utils.data.TensorDataset(indices, mask, y)
return dataset
# In[83]:
def bert_fine_tune_phi(text):
return text
# In[85]:
model_try=HfBertClassifier_all.from_pickle("bert_model_deploy_1.pt")
# In[112]:
#model_try.predict(["The 1st half was bad and the 2nd half was good","Wow what an amazing movie"])
# In[93]:
tokenizer = TreebankWordTokenizer()
def treebank_tokenize_detokenize(s):
return ' '.join(tokenizer.tokenize(s))
# In[110]:
def predict_1(text):
text_tokenized=treebank_tokenize_detokenize(text)
return model_try.predict([text_tokenized])[0]
import gradio as gr
iface = gr.Interface(fn=predict_1, inputs="text", outputs="text")
iface.launch()
# In[114]:
#predict_1("The 1st half was good but the 2nd half was bad")
# In[ ]:
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