data/data_loader.py

import json
import os
import pickle
import random
from pathlib import Path
import time
import wfdb
import numpy as np
import torch
from PIL import Image
from torch.utils.data import Dataset
from torchvision.transforms import ColorJitter
from scipy.io import loadmat
from load_class import get_temp_qa, change_ecg_to_qa, prepare_ecg_qa_data
from utils import set_device
import matplotlib.pyplot as plt
import argparse
from meta_trainer import MetaTrainer
import warnings
from transformers import AutoTokenizer

warnings.filterwarnings("ignore")

torch.manual_seed(222)
torch.cuda.manual_seed_all(222)
np.random.seed(222)

PROJECT_ROOT = str(Path.cwd().parent.parent)  # project path
LOG_PATH = PROJECT_ROOT + "/logs/"
MODELS_PATH = PROJECT_ROOT + "/models/"

class FSL_ECG_QA_DataLoader(Dataset):
    """
    This is DataLoader for episodic training on FSL_ECG_QA dataset
    NOTICE: meta-learning is different from general supervised learning, especially the concept of batch and set.
    batch: contains several sets / tasks
    sets: conains n_way * k_shot for meta-train set, n_way * k_query for meta-test set.
    """

    def __init__(self, mode, batchsz, n_way, k_shot, k_query, seq_len, seq_len_a, repeats, tokenizer,
                 prefix_length, startidx=0, all_ids=None, in_templates=None, prompt=1, paraphrased_path="",test_dataset=""):
        self.batchsz = batchsz  
        self.n_way = n_way  
        self.k_shot = k_shot  
        self.k_query = k_query  
        self.repeats = repeats
        self.setsz = self.n_way * self.k_shot if self.repeats == 0 else self.n_way * self.k_shot * (self.repeats + 1)
        self.querysz = self.n_way * self.k_query  # number of samples per set for evaluation
        self.seq_len = seq_len  # sentence seq length
        self.seq_len_a = seq_len_a
        self.prefix_length = prefix_length
        self.startidx = startidx  # index label not from 0, but from startidx
        self.device = set_device()
        print('shuffle DB: %s, b:%d, %d-way, %d-shot, %d-query, %d-repeats' % (mode, batchsz, n_way, k_shot,
                                                                                          k_query, repeats))
        self.gpt_tokenizer = tokenizer
        self.mode = mode
        self.all_ids = all_ids
        self.prompt = prompt
        self.test_dataset=test_dataset
        
        json_data_ecg = change_ecg_to_qa(all_ids, in_templates, paraphrased_path, test_dataset=test_dataset)
      
        self.data = []
        self.img2caption = {}
        
        for i, (category_name, ecg_q_as) in enumerate(json_data_ecg.items()):
            self.data.append(ecg_q_as)

        self.cls_num = len(self.data)
        print("self.cls_num", self.mode, self.cls_num)
        
        self.create_batch(self.batchsz)


    def create_batch(self, batchsz):
        """
        create batch for meta-learning.
        ×episode× here means batch, and it means how many sets we want to retain.
        :param episodes: batch size
        :return:
        """
        self.support_x_batch = []  # support set batch
        self.query_x_batch = []  # query set batch
        # Creating of tasks; batchsz is the num. of iterations when sampling from the task distribution
        for b in range(batchsz):  # for each batch
            # 1.select n_way classes randomly
            selected_cls = np.random.choice(self.cls_num, self.n_way, replace=False)  # no duplicate
            support_x = []
            query_x = []
            for cls in selected_cls:
                selected_question = np.random.choice(len(self.data[cls]), 1)[0]
                selected_imgs_idx = np.random.choice(len(self.data[cls][selected_question]), self.k_shot + self.k_query)
                np.random.shuffle(selected_imgs_idx)
                indexDtrain = np.array(selected_imgs_idx[:self.k_shot])  # idx for Dtrain
                indexDtest = np.array(selected_imgs_idx[self.k_shot:])  # idx for Dtest
                support_x.append(
                    np.array(self.data[cls][selected_question])[indexDtrain].tolist())  # get all images filename for current Dtrain
                query_x.append(np.array(self.data[cls][selected_question])[indexDtest].tolist())
                if self.repeats > 0:
                    for i in range(self.repeats):
                        support_x.append(np.array(self.data[cls][selected_question])[indexDtrain].tolist())

            # shuffle the corresponding relation between support set and query set
            random.shuffle(support_x)
            random.shuffle(query_x)

            self.support_x_batch.append(support_x)  # append set to current sets
            self.query_x_batch.append(query_x)  # append sets to current sets
                            
            # shuffle the corresponding relation between support set and query set
            random.shuffle(support_x)
            random.shuffle(query_x)
            self.support_x_batch.append(support_x)  # append set to current sets
            self.query_x_batch.append(query_x)  # append sets to current sets

    def get_ptbxl_data_path(self, ecg_id):
        return os.path.join(
            f"{int(ecg_id / 1000) * 1000 :05d}",
            f"{ecg_id:05d}_hr"
        )
        
    def gen_prompt(self, q_str):    
        if self.prompt == 1:
            token_p = "Question: "+q_str+"Answer: "
        if self.prompt == 2:
            token_p = q_str
        if self.prompt == 3:
            token_p = q_str+"the answer can be both, none or in question."
        return token_p
        
    def __getitem__(self, index):
        """
        index means index of sets, 0<= index <= batchsz-1
        :param index:
        :return:
        """
        support_x = torch.FloatTensor(self.setsz, 12, 2500)
        query_x = torch.FloatTensor(self.querysz, 12, 2500)
        
        support_y_q = []
        support_y_a = []
        support_y_q_mask = []
        support_y_a_mask = []
        query_y_q = []
        query_y_a = []
        query_y_q_mask = []
        query_y_a_mask = []
        
        flatten_support_x = [f"/gpfs/home1/jtang1/multimodal_fsl_99/process_ptbxl2/{self.get_ptbxl_data_path(sample['ecg_id'][0])}"
                             for sublist in self.support_x_batch[index] for sample in sublist]
        flatten_query_x = [f"/gpfs/home1/jtang1/multimodal_fsl_99/process_ptbxl2/{self.get_ptbxl_data_path(sample['ecg_id'][0])}"
                           for sublist in self.query_x_batch[index] for sample in sublist]
        
        for sublist in self.support_x_batch[index]:
            for sample in sublist:
                q_str = sample["question"].lower()
                for num_a, content in enumerate(sample["answer"]):
                    if num_a != 0:
                        a_str += ", " + content.lower()
                    else:
                        a_str = content.lower()
                
                q_str_tokenized = self.gpt_tokenizer(self.gen_prompt(q_str), return_tensors="pt")['input_ids']

                caption_padded_q, mask_0_q = pad_tokens(q_str_tokenized, self.seq_len, self.prefix_length,
                                                self.gpt_tokenizer.eos_token_id)
                support_y_q.append(caption_padded_q)
                support_y_q_mask.append(mask_0_q)
                
                a_str_tokenized = self.gpt_tokenizer(a_str, return_tensors="pt")['input_ids']
                caption_padded_a, mask_0_a = pad_tokens(a_str_tokenized, self.seq_len_a, self.prefix_length,
                                                self.gpt_tokenizer.eos_token_id)
                support_y_a.append(caption_padded_a)
                support_y_a_mask.append(mask_0_a)
                
        support_y_q = torch.stack(support_y_q)
        support_y_a = torch.stack(support_y_a)
        support_y_q_mask = torch.stack(support_y_q_mask)
        support_y_a_mask = torch.stack(support_y_a_mask)
        
        for sublist in self.query_x_batch[index]:
            for sample in sublist:
                q_str = sample["question"].lower()
                for num_a, content in enumerate(sample["answer"]):
                    if num_a != 0:
                        a_str += ", " + content.lower()
                    else:
                        a_str = content.lower()

                q_str_tokenized = self.gpt_tokenizer(self.gen_prompt(q_str), return_tensors="pt")['input_ids']
                caption_padded_q, mask_0_q = pad_tokens(q_str_tokenized, self.seq_len, self.prefix_length,
                                                        self.gpt_tokenizer.eos_token_id)
                query_y_q.append(caption_padded_q)
                query_y_q_mask.append(mask_0_q)

                a_str_tokenized = self.gpt_tokenizer(a_str, return_tensors="pt")['input_ids']
                caption_padded_a, mask_0_a = pad_tokens(a_str_tokenized, self.seq_len_a, self.prefix_length,
                                                        self.gpt_tokenizer.eos_token_id)
                query_y_a.append(caption_padded_a)
                query_y_a_mask.append(mask_0_a)

        query_y_q = torch.stack(query_y_q)
        query_y_q_mask = torch.stack(query_y_q_mask)
        query_y_a = torch.stack(query_y_a)
        query_y_a_mask = torch.stack(query_y_a_mask)

        # Reading of ecgs:
        for i, path in enumerate(flatten_support_x):
            ecg = loadmat(path)['feats']
            support_x[i] = torch.tensor(ecg)

        for i, path in enumerate(flatten_query_x):
            ecg = loadmat(path)['feats']
            query_x[i] = torch.tensor(ecg)

        return support_x, support_y_q, support_y_a, support_y_q_mask, support_y_a_mask, flatten_support_x, query_x, query_y_q, query_y_a, query_y_q_mask, query_y_a_mask, flatten_query_x

    def __len__(self):
        return self.batchsz


def pad_tokens(tokens, seq_len, prefix_length, eos_token_id):
    tokens = tokens.squeeze(0)
    padding = seq_len - tokens.shape[0]
    if padding > 0:
        tokens = torch.cat((tokens, torch.zeros(padding, dtype=torch.int64) - 1))
    elif padding < 0:
        tokens = tokens[:seq_len]
    mask = tokens.ge(0)  # mask is zero where we out of sequence
    tokens[~mask] = eos_token_id
    mask = mask.float()
    mask = torch.cat((torch.ones(prefix_length), mask), dim=0)  # adding prefix mask
    return tokens, mask 
    
    
if __name__ == '__main__':
    argparser = argparse.ArgumentParser()

    argparser.add_argument('--experiment_id', type=int, default=666)
    argparser.add_argument('--batchsz_train', type=int, default=10000)
    argparser.add_argument('--batchsz_test', type=int, default=1000)
    argparser.add_argument('--model_name', type=str, help="path to model download from hugging face", default="path/to/model")
    argparser.add_argument('--update_step', type=int, help='task-level inner update steps', default=5)
    argparser.add_argument('--update_step_test', type=int, help='update steps for finetunning', default=15)
    
    argparser.add_argument('--paraphrased_path', type=str, default='path/to/paraphrased', 
                          help='path to ./paraphrased containing trian/val/test ECG-QA json files')
    argparser.add_argument('--question_type', type=str, help='question types, single-verify, single-choose, single-query,all', default='single-verify')
    argparser.add_argument('--epoch', type=int, help='epoch number', default=10000)
    argparser.add_argument('--n_way', type=int, help='n way', default=5)
    argparser.add_argument('--k_spt', type=int, help='k shot for support set', default=5)
    argparser.add_argument('--k_qry', type=int, help='k shot for query set', default=5)
    argparser.add_argument('--prompt', type=int, help='1,Question: +q_str+Answer:,2,q_str,3,q_str+the answer can be both, none or in question.', default=1)
    argparser.add_argument('--dif_exp', type=int, help='0,same_exp,1,dif_exp', default=0)
    argparser.add_argument('--frozen_gpt', type=int, help='0,unfrozen_gpt,1,frozen_gpt', default=1)  
    argparser.add_argument('--frozen_features', type=int, help='0,unfrozen_features,1,frozen_features', default=1)    
    argparser.add_argument('--repeats', type=int, help='repeats for support set', default=0)
    argparser.add_argument('--seq_len', help='for padding batch', type=int, default=30) 
    argparser.add_argument('--seq_len_a', help='for padding batch', type=int, default=30)
    argparser.add_argument('--prefix_length', type=int, default=4)
    argparser.add_argument('--mapper_type', type=str, help='ATT MLP', default="MLP")
    argparser.add_argument('--task_num', type=int, help='meta batch size, namely task num', default=1)
    argparser.add_argument('--meta_lr', type=float, help='meta-level outer learning rate', default=5e-4)
    argparser.add_argument('--update_lr', type=float, help='task-level inner update learning rate', default=0.05)
    argparser.add_argument('--test_dataset', type=str, default="ptb-xl", choices=["ptb-xl", "mimic"], help='Dataset to use (ptb-xl or mimic)')
    args = argparser.parse_args()

    class_qa, train_temp, test_temp = prepare_ecg_qa_data(args)
    
    device = set_device()
    meta = MetaTrainer(args, args.experiment_id, is_pretrained=False).to(device)
    params = list(filter(lambda p: p.requires_grad, meta.model.parameters()))
    params_summed = sum(p.numel() for p in params)
    print("Total num of params: {} ".format(params_summed))
    gpt_tokenizer = AutoTokenizer.from_pretrained(args.model_name)
    data_loader_train = FSL_ECG_QA_DataLoader(mode='train', n_way=args.n_way, k_shot=args.k_spt,k_query=args.k_qry, batchsz=args.batchsz_train,
                                      seq_len=args.seq_len, seq_len_a=args.seq_len_a,repeats=args.repeats, tokenizer=gpt_tokenizer,
                                      prefix_length=args.prefix_length,all_ids=class_qa, in_templates=train_temp, prompt=args.prompt,
                                      paraphrased_path= args.paraphrased_path, test_dataset=args.test_dataset)
    data_loader_test  = FSL_ECG_QA_DataLoader(mode='test', n_way=args.n_way, k_shot=args.k_spt,k_query=args.k_qry, batchsz=args.batchsz_train,
                                      seq_len=args.seq_len, seq_len_a=args.seq_len_a,repeats=args.repeats, tokenizer=gpt_tokenizer,
                                      prefix_length=args.prefix_length,all_ids=class_qa, in_templates=test_temp, prompt=args.prompt,
                                      paraphrased_path= args.paraphrased_path, test_dataset=args.test_dataset)
    batch = next(iter(data_loader_train))
    
    if isinstance(batch, dict):
        for key, value in batch.items():
            print(f"{key}: {value}")
    elif isinstance(batch, (list, tuple)):
        for i, item in enumerate(batch):
            print(f"Item {i}: {item}")
    else:
        print(batch)