Module imodelsx.d3.step1_get_extreme

Functions

def cv(pos, neg, K)
Expand source code
def cv(pos, neg, K):
    return [
        {
            'train_pos': [p for i, p in enumerate(pos) if i % K != k],
            'train_neg': [n for i, n in enumerate(neg) if i % K != k],
            'test_pos': [p for i, p in enumerate(pos) if i % K == k],
            'test_neg': [n for i, n in enumerate(neg) if i % K == k],
        }
        for k in range(K)
    ]
def get_spans(tok, text)
Expand source code
def get_spans(tok, text):
    be = tok(text)
    length = len(be['input_ids'])
    results = []
    for i in range(length):
        if i in (0, length - 1):
            results.append((0, 0))
        else:
            start, end = be.token_to_chars(i)
            results.append((start, end))
    return results
def return_extreme_values(pos, neg, num_steps=2000, num_folds=4, batch_size=16)
Expand source code
def return_extreme_values(pos, neg, num_steps=2000, num_folds=4, batch_size=16):
    pos2score, neg2score = {}, {}
    pos2highlight, neg2highlight = {}, {}
    
    for fold_idx, cv_dict in enumerate(cv(pos, neg, num_folds)):
        print('fold', fold_idx + 1, '/', num_folds)
        test_scores = train_and_eval(cv_dict, num_steps, batch_size)
        for pos_text, score, highlight in zip(cv_dict['test_pos'], test_scores['test_pos_scores'], test_scores['test_pos_highlight']):
            pos2score[pos_text] = score
            pos2highlight[pos_text] = highlight
        for neg_text, score, highlight in zip(cv_dict['test_neg'], test_scores['test_neg_scores'], test_scores['test_neg_highlight']):
            neg2score[neg_text] = score
            neg2highlight[neg_text] = highlight
    return {
        'pos2score': pos2score,
        'neg2score': neg2score,
        'pos2highlight': pos2highlight,
        'neg2highlight': neg2highlight
    }
def train_and_eval(cv_dict, num_steps=2000, batch_size=16)
Expand source code
def train_and_eval(cv_dict, num_steps=2000, batch_size=16):
    max_length = 128
    train_data_dicts = list(chain(
        [{'input': x, 'label': 1} for x in cv_dict['train_pos']], 
        [{'input': x, 'label': 0} for x in cv_dict['train_neg']], 
    ))
    # model = RobertaForSequenceClassification.from_pretrained(pretrain_model).to(device)
    # model = RoBERTaSeq().to(device)
    model = RoBERTaSeqAttn().to(device)
    no_decay = ['bias', 'LayerNorm.weight']
    optimizer_grouped_parameters = [
        {'params': [p for n, p in model.named_parameters() if not any(nd in n for nd in no_decay)],
         'weight_decay': 0.01},
        {'params': [p for n, p in model.named_parameters() if any(nd in n for nd in no_decay)], 'weight_decay': 0.0}
    ]
    optimizer = AdamW(optimizer_grouped_parameters, lr=5e-5)
    scheduler = get_linear_schedule_with_warmup(optimizer, 400, num_steps)
    tok = AutoTokenizer.from_pretrained(pretrain_model)
    
    for step in tqdm.trange(num_steps):
        random.shuffle(train_data_dicts)
        input_texts = [d['input'] for d in train_data_dicts[:batch_size]]
        inputs = tok(input_texts, return_tensors='pt', truncation=True, max_length=max_length, padding=True).to(device)
        labels = torch.tensor([d['label'] for d in train_data_dicts[:batch_size]]).to(device)
        outputs = model(**inputs, labels=labels)
        loss = outputs['loss']
        loss.backward()
        if step % 2 == 1:
            optimizer.step()
            scheduler.step()
            optimizer.zero_grad()

    def evaluate(texts):
        all_logits, all_highlights = [], []
        cur_start = 0
        while cur_start < len(texts):
            texts_ = texts[cur_start:cur_start + batch_size]
            inputs = tok(texts_, return_tensors='pt', truncation=True, max_length=max_length, padding=True).to(device)
            model_output_dict = model(**inputs)
            logits = lsm(model_output_dict['logits'].detach().cpu()).numpy().tolist()
            all_highlights.extend(model_output_dict['highlight'])
            all_logits.extend(logits)
            cur_start += batch_size
        assert len(all_logits) == len(texts)
        
        all_spans = [get_spans(tok, text) for text in texts]
        assert len(all_spans) == len(all_highlights)
        for a, b in zip(all_spans, all_highlights):
            assert len(a) == len(b) or len(a) >= max_length
        
        highlights = [
            {s: h for s, h in zip(spans, highlights) if s != (0, 0)} 
            for spans, highlights in zip(all_spans, all_highlights)
        ]
        
        return {
            'logits': np.array(all_logits),
            'highlights': highlights
        }
    
    pos_eval_dict = evaluate(cv_dict['test_pos'])
    pos_logits, pos_highlights = pos_eval_dict['logits'][:,1], pos_eval_dict['highlights']
    
    neg_eval_dict = evaluate(cv_dict['test_neg'])
    neg_logits, neg_highlights = neg_eval_dict['logits'][:,0], neg_eval_dict['highlights']
    
    return {
        'test_pos_scores': pos_logits,
        'test_neg_scores': neg_logits,
        'test_pos_highlight': pos_highlights,
        'test_neg_highlight': neg_highlights 
    }

Classes

class RoBERTaSeq
Expand source code
class RoBERTaSeq(nn.Module):
    
    def __init__(self):
        super().__init__()
        self.model = AutoModelForSequenceClassification.from_pretrained(pretrain_model)
    
    def forward(self, **inputs):
        model_outputs = self.model(**inputs)
        model_output_dict = vars(model_outputs)
        
        seq_lengths = torch.sum(inputs['attention_mask'], dim=-1).detach().cpu().numpy()
        model_output_dict['highlight'] = [[1./seq_length for _ in range(seq_length)] for seq_length in seq_lengths]
        return model_output_dict

Base class for all neural network modules.

Your models should also subclass this class.

Modules can also contain other Modules, allowing them to be nested in a tree structure. You can assign the submodules as regular attributes::

import torch.nn as nn
import torch.nn.functional as F


class Model(nn.Module):
    def __init__(self) -> None:
        super().__init__()
        self.conv1 = nn.Conv2d(1, 20, 5)
        self.conv2 = nn.Conv2d(20, 20, 5)

    def forward(self, x):
        x = F.relu(self.conv1(x))
        return F.relu(self.conv2(x))

Submodules assigned in this way will be registered, and will also have their parameters converted when you call :meth:to, etc.

Note

As per the example above, an __init__() call to the parent class must be made before assignment on the child.

:ivar training: Boolean represents whether this module is in training or evaluation mode. :vartype training: bool

Initialize internal Module state, shared by both nn.Module and ScriptModule.

Ancestors

  • torch.nn.modules.module.Module

Methods

def forward(self, **inputs) ‑> Callable[..., Any]
Expand source code
def forward(self, **inputs):
    model_outputs = self.model(**inputs)
    model_output_dict = vars(model_outputs)
    
    seq_lengths = torch.sum(inputs['attention_mask'], dim=-1).detach().cpu().numpy()
    model_output_dict['highlight'] = [[1./seq_length for _ in range(seq_length)] for seq_length in seq_lengths]
    return model_output_dict

Define the computation performed at every call.

Should be overridden by all subclasses.

Note

Although the recipe for forward pass needs to be defined within this function, one should call the :class:Module instance afterwards instead of this since the former takes care of running the registered hooks while the latter silently ignores them.

class RoBERTaSeqAttn
Expand source code
class RoBERTaSeqAttn(nn.Module):
    
    def __init__(self):
        super().__init__()
        self.model = AutoModel.from_pretrained(pretrain_model)
        self.clf_layer = nn.Linear(self.model.config.hidden_size, 2)
        self.attn_layer = nn.Linear(self.model.config.hidden_size, 1)
        self.sm = nn.Softmax(dim=-1)
        self.lsm = nn.LogSoftmax(dim=-1)
        self.loss_func = nn.NLLLoss()
        
    
    def forward(self, **inputs):
        last_hidden_state = self.model(input_ids=inputs['input_ids'], 
                                   attention_mask=inputs['attention_mask']).last_hidden_state
        
        attn_logits = self.attn_layer(last_hidden_state).squeeze(axis=-1)
        attn_logits[inputs['attention_mask'] == 0] = float('-inf')
        attention = self.sm(attn_logits)
        
        seq_lengths = torch.sum(inputs['attention_mask'], dim=-1).detach().cpu().numpy()
        aggregated_repr = torch.einsum('bs,bsh->bh', attention, last_hidden_state)
        
        logits = self.lsm(self.clf_layer(aggregated_repr))
        
        return_dict = {
            'logits': logits,
            'highlight': [attention[i][:s].detach().cpu().numpy() for i, s in enumerate(seq_lengths)]
        }
        if 'labels' in inputs:
            loss = self.loss_func(logits, inputs['labels'])
            return_dict['loss'] = loss
        return return_dict

Base class for all neural network modules.

Your models should also subclass this class.

Modules can also contain other Modules, allowing them to be nested in a tree structure. You can assign the submodules as regular attributes::

import torch.nn as nn
import torch.nn.functional as F


class Model(nn.Module):
    def __init__(self) -> None:
        super().__init__()
        self.conv1 = nn.Conv2d(1, 20, 5)
        self.conv2 = nn.Conv2d(20, 20, 5)

    def forward(self, x):
        x = F.relu(self.conv1(x))
        return F.relu(self.conv2(x))

Submodules assigned in this way will be registered, and will also have their parameters converted when you call :meth:to, etc.

Note

As per the example above, an __init__() call to the parent class must be made before assignment on the child.

:ivar training: Boolean represents whether this module is in training or evaluation mode. :vartype training: bool

Initialize internal Module state, shared by both nn.Module and ScriptModule.

Ancestors

  • torch.nn.modules.module.Module

Methods

def forward(self, **inputs) ‑> Callable[..., Any]
Expand source code
def forward(self, **inputs):
    last_hidden_state = self.model(input_ids=inputs['input_ids'], 
                               attention_mask=inputs['attention_mask']).last_hidden_state
    
    attn_logits = self.attn_layer(last_hidden_state).squeeze(axis=-1)
    attn_logits[inputs['attention_mask'] == 0] = float('-inf')
    attention = self.sm(attn_logits)
    
    seq_lengths = torch.sum(inputs['attention_mask'], dim=-1).detach().cpu().numpy()
    aggregated_repr = torch.einsum('bs,bsh->bh', attention, last_hidden_state)
    
    logits = self.lsm(self.clf_layer(aggregated_repr))
    
    return_dict = {
        'logits': logits,
        'highlight': [attention[i][:s].detach().cpu().numpy() for i, s in enumerate(seq_lengths)]
    }
    if 'labels' in inputs:
        loss = self.loss_func(logits, inputs['labels'])
        return_dict['loss'] = loss
    return return_dict

Define the computation performed at every call.

Should be overridden by all subclasses.

Note

Although the recipe for forward pass needs to be defined within this function, one should call the :class:Module instance afterwards instead of this since the former takes care of running the registered hooks while the latter silently ignores them.