Project-I/data/dataloader.py

171 lines
6.1 KiB
Python

from utils.normalizer import normalize_dataset
import numpy as np
import gc
import torch
def get_dataloader(config, data):
config = config['data']
L, N, F = data.shape # 数据形状
# Step 1: data -> x,y
x = add_window_x(data, config['lag'], config['horizon'])
y = add_window_y(data, config['lag'], config['horizon'])
del data
gc.collect()
# Step 2: time_in_day, day_in_week -> day, week
time_in_day = [i % config['steps_per_day'] / config['steps_per_day'] for i in range(L)]
time_in_day = np.tile(np.array(time_in_day), [1, N, 1]).transpose((2, 1, 0))
day_in_week = [(i // config['steps_per_day']) % config['days_per_week'] for i in range(L)]
day_in_week = np.tile(np.array(day_in_week), [1, N, 1]).transpose((2, 1, 0))
x_day = add_window_x(time_in_day, config['lag'], config['horizon'])
x_week = add_window_x(day_in_week, config['lag'], config['horizon'])
# Step 3 day, week, x, y --> x, y
x = np.concatenate([x, x_day, x_week], axis=-1)
del x_day, x_week
gc.collect()
# Step 4 x,y --> x_train, x_val, x_test, y_train, y_val, y_test
if config['test_ratio'] > 1:
x_train, x_val, x_test = split_data_by_days(x, config['val_ratio'], config['test_ratio'])
else:
x_train, x_val, x_test = split_data_by_ratio(x, config['val_ratio'], config['test_ratio'])
del x
gc.collect()
# Multi-channel normalization - each channel normalized independently
input_channels = x_train[..., :config['input_dim']]
num_channels = input_channels.shape[-1]
# Initialize scalers for each channel
scalers = []
# Normalize each channel independently
for channel_idx in range(num_channels):
channel_data = input_channels[..., channel_idx:channel_idx+1]
scaler = normalize_dataset(channel_data, config['normalizer'], config['column_wise'])
scalers.append(scaler)
# Apply transformation to each channel
x_train[..., channel_idx:channel_idx+1] = scaler.transform(channel_data)
x_val[..., channel_idx:channel_idx+1] = scaler.transform(x_val[..., channel_idx:channel_idx+1])
x_test[..., channel_idx:channel_idx+1] = scaler.transform(x_test[..., channel_idx:channel_idx+1])
y_day = add_window_y(time_in_day, config['lag'], config['horizon'])
y_week = add_window_y(day_in_week, config['lag'], config['horizon'])
del time_in_day, day_in_week
gc.collect()
y = np.concatenate([y, y_day, y_week], axis=-1)
del y_day, y_week
gc.collect()
# Split Y
if config['test_ratio'] > 1:
y_train, y_val, y_test = split_data_by_days(y, config['val_ratio'], config['test_ratio'])
else:
y_train, y_val, y_test = split_data_by_ratio(y, config['val_ratio'], config['test_ratio'])
del y
gc.collect()
# Step 5: x_train y_train x_val y_val x_test y_test --> train val test
# train_dataloader = data_loader(x_train[..., :args['input_dim']], y_train[..., :args['input_dim']], args['batch_size'], shuffle=True, drop_last=True)
train_dataloader = data_loader(x_train, y_train, config['batch_size'], shuffle=True, drop_last=True)
del x_train, y_train
gc.collect()
# val_dataloader = data_loader(x_val[..., :args['input_dim']], y_val[..., :args['input_dim']], args['batch_size'], shuffle=False, drop_last=True)
val_dataloader = data_loader(x_val, y_val, config['batch_size'], shuffle=False, drop_last=True)
del x_val, y_val
gc.collect()
# test_dataloader = data_loader(x_test[..., :args['input_dim']], y_test[..., :args['input_dim']], args['batch_size'], shuffle=False, drop_last=False)
test_dataloader = data_loader(x_test, y_test, config['batch_size'], shuffle=False, drop_last=False)
del x_test, y_test
gc.collect()
return train_dataloader, val_dataloader, test_dataloader, scalers
def split_data_by_days(data, val_days, test_days, interval=30):
t = int((24 * 60) / interval)
test_data = data[-t * int(test_days):]
val_data = data[-t * int(test_days + val_days):-t * int(test_days)]
train_data = data[:-t * int(test_days + val_days)]
return train_data, val_data, test_data
def split_data_by_ratio(data, val_ratio, test_ratio):
data_len = data.shape[0]
test_data = data[-int(data_len * test_ratio):]
val_data = data[-int(data_len * (test_ratio + val_ratio)):-int(data_len * test_ratio)]
train_data = data[:-int(data_len * (test_ratio + val_ratio))]
return train_data, val_data, test_data
def data_loader(X, Y, batch_size, shuffle=True, drop_last=True):
device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
X = torch.tensor(X, dtype=torch.float32, device=device)
Y = torch.tensor(Y, dtype=torch.float32, device=device)
data = torch.utils.data.TensorDataset(X, Y)
dataloader = torch.utils.data.DataLoader(data, batch_size=batch_size,
shuffle=shuffle, drop_last=drop_last)
return dataloader
def add_window_x(data, window=3, horizon=1, single=False):
"""
Generate windowed X values from the input data.
:param data: Input data, shape [B, ...]
:param window: Size of the sliding window
:param horizon: Horizon size
:param single: If True, generate single-step windows, else multi-step
:return: X with shape [B, W, ...]
"""
length = len(data)
end_index = length - horizon - window + 1
x = [] # Sliding windows
index = 0
while index < end_index:
x.append(data[index:index + window])
index += 1
return np.array(x)
def add_window_y(data, window=3, horizon=1, single=False):
"""
Generate windowed Y values from the input data.
:param data: Input data, shape [B, ...]
:param horizon: Horizon size
:param single: If True, generate single-step windows, else multi-step
:return: Y with shape [B, H, ...]
"""
length = len(data)
end_index = length - horizon - window + 1
y = [] # Horizon values
index = 0
while index < end_index:
if single:
y.append(data[index + window + horizon - 1:index + window + horizon])
else:
y.append(data[index + window:index + window + horizon])
index += 1
return np.array(y)