TrafficWheel/dataloader/EXPdataloader.py

200 lines
6.8 KiB
Python
Executable File

import numpy as np
import torch
from utils.normalization import normalize_dataset
from dataloader.data_selector import load_st_dataset
def get_dataloader(args, normalizer="std", single=True):
# args should now include 'cycle'
data = load_st_dataset(args["type"], args["sample"]) # [T, N, F]
L, N, F = data.shape
# compute cycle index
cycle_arr = np.arange(L) % args["cycle"] # length-L array
# Step 1: sliding windows for X and Y
x = add_window_x(data, args["lag"], args["horizon"], single)
y = add_window_y(data, args["lag"], args["horizon"], single)
# window count = M = L - lag - horizon + 1
M = x.shape[0]
# Step 2: time features
time_in_day = np.tile(
np.array([i % args["steps_per_day"] / args["steps_per_day"] for i in range(L)]),
(N, 1),
).T.reshape(L, N, 1)
day_in_week = np.tile(
np.array(
[(i // args["steps_per_day"]) % args["days_per_week"] for i in range(L)]
),
(N, 1),
).T.reshape(L, N, 1)
x_day = add_window_x(time_in_day, args["lag"], args["horizon"], single)
x_week = add_window_x(day_in_week, args["lag"], args["horizon"], single)
x = np.concatenate([x, x_day, x_week], axis=-1)
# del x_day, x_week
# gc.collect()
# Step 3: extract cycle index per window: take value at end of sequence
cycle_win = np.array([cycle_arr[i + args["lag"]] for i in range(M)]) # shape [M]
# Step 4: split into train/val/test
if args["test_ratio"] > 1:
x_train, x_val, x_test = split_data_by_days(
x, args["val_ratio"], args["test_ratio"]
)
y_train, y_val, y_test = split_data_by_days(
y, args["val_ratio"], args["test_ratio"]
)
c_train, c_val, c_test = split_data_by_days(
cycle_win, args["val_ratio"], args["test_ratio"]
)
else:
x_train, x_val, x_test = split_data_by_ratio(
x, args["val_ratio"], args["test_ratio"]
)
y_train, y_val, y_test = split_data_by_ratio(
y, args["val_ratio"], args["test_ratio"]
)
c_train, c_val, c_test = split_data_by_ratio(
cycle_win, args["val_ratio"], args["test_ratio"]
)
# del x, y, cycle_win
# gc.collect()
# Step 5: normalization on X only
scaler = normalize_dataset(
x_train[..., : args["input_dim"]], normalizer, args["column_wise"]
)
x_train[..., : args["input_dim"]] = scaler.transform(
x_train[..., : args["input_dim"]]
)
x_val[..., : args["input_dim"]] = scaler.transform(x_val[..., : args["input_dim"]])
x_test[..., : args["input_dim"]] = scaler.transform(
x_test[..., : args["input_dim"]]
)
# add time features to Y
y_day = add_window_y(time_in_day, args["lag"], args["horizon"], single)
y_week = add_window_y(day_in_week, args["lag"], args["horizon"], single)
y = np.concatenate([y, y_day, y_week], axis=-1)
# del y_day, y_week, time_in_day, day_in_week
# gc.collect()
# split Y time-augmented
if args["test_ratio"] > 1:
y_train, y_val, y_test = split_data_by_days(
y, args["val_ratio"], args["test_ratio"]
)
else:
y_train, y_val, y_test = split_data_by_ratio(
y, args["val_ratio"], args["test_ratio"]
)
# del y
# Step 6: create dataloaders including cycle index
train_loader = data_loader_with_cycle(
x_train, y_train, c_train, args["batch_size"], shuffle=True, drop_last=True
)
val_loader = data_loader_with_cycle(
x_val, y_val, c_val, args["batch_size"], shuffle=False, drop_last=True
)
test_loader = data_loader_with_cycle(
x_test, y_test, c_test, args["batch_size"], shuffle=False, drop_last=False
)
return train_loader, val_loader, test_loader, scaler
def data_loader_with_cycle(X, Y, C, batch_size, shuffle=True, drop_last=True):
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
X_t = torch.tensor(X, dtype=torch.float32, device=device)
Y_t = torch.tensor(Y, dtype=torch.float32, device=device)
C_t = torch.tensor(C, dtype=torch.long, device=device).unsqueeze(-1) # [B,1]
dataset = torch.utils.data.TensorDataset(X_t, Y_t, C_t)
loader = torch.utils.data.DataLoader(
dataset, batch_size=batch_size, shuffle=shuffle, drop_last=drop_last
)
return loader
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 window: Size of the sliding window
: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)
if __name__ == "__main__":
res = load_st_dataset("SD", 1)
k = 1