tutorial from ai is uhjhhhhh

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.conda/ .conda*/
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{
"recommendations": ["ms-python.python", "ms-toolsai.jupyter"]
}
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"""
This script demonstrates how to port a TensorFlow LSTM model to PyTorch.
It includes detailed explanations for every step.
"""
# Step 1: Import necessary libraries
# ----------------------------------
# PyTorch is the core library for building and training neural networks.
# Torch.nn contains modules for defining layers and loss functions.
# Torch.optim provides optimizers like Adam for training.
import matplotlib.pyplot as plt
import numpy as np
import torch
from sklearn.model_selection import train_test_split
from sklearn.preprocessing import MinMaxScaler
from torch import nn, optim
from torch.utils.data import DataLoader, TensorDataset
from load_data import load_this_data
# Step 2: Data Preparation
# ------------------------
# In PyTorch, data must be converted into tensors. We'll simulate the data
# preprocessing steps from your TensorFlow code.
# Simulate some data (replace this with your actual data loading logic)
np.random.seed(42) # For reproducibility
# data = np.sin(np.linspace(0, 100, 1000)) # Example: Sine wave data
# data = data.reshape(-1, 1) # Reshape to (samples, features)
# Load the dataset (replace "dataset.csv" with your actual file path)
data = load_this_data("dataset.csv")
# Extract the "Humidity" column as the target variable
data = data["Humidity"].values.reshape(-1, 1)
# Normalize the data using MinMaxScaler (same as in TensorFlow)
scaler = MinMaxScaler()
data_scaled = scaler.fit_transform(data)
# Define lookback window (sequence length for LSTM)
n_lookback = 100 # Number of past timesteps to consider
n_features = 1 # Number of features (e.g., 1 for univariate time series)
# Helper function to create sequences
def create_sequences(data, n_lookback):
"""
Create sequences of length n_lookback for LSTM input.
Args:
data: Scaled data as a NumPy array or PyTorch tensor.
n_lookback: Number of past timesteps to consider.
Returns:
x: Input sequences of shape (num_samples, n_lookback, n_features).
y: Target values of shape (num_samples, 1).
"""
x, y = [], []
for i in range(len(data) - n_lookback):
x.append(data[i : i + n_lookback])
y.append(data[i + n_lookback])
return np.array(x), np.array(y)
# Split into training and testing sets (80% train, 20% test)
train_data, test_data = train_test_split(data_scaled, test_size=0.2, shuffle=False)
# Create sequences for training and testing
train_x, train_y = create_sequences(train_data, n_lookback)
test_x, test_y = create_sequences(test_data, n_lookback)
# Convert sequences to PyTorch tensors
train_x = torch.tensor(train_x, dtype=torch.float32)
train_y = torch.tensor(train_y, dtype=torch.float32)
test_x = torch.tensor(test_x, dtype=torch.float32)
test_y = torch.tensor(test_y, dtype=torch.float32)
# Create datasets and dataloaders
train_dataset = TensorDataset(train_x, train_y)
test_dataset = TensorDataset(test_x, test_y)
train_loader = DataLoader(train_dataset, batch_size=128, shuffle=True)
test_loader = DataLoader(test_dataset, batch_size=128, shuffle=False)
# Step 3: Define the LSTM Model
# -----------------------------
# PyTorch models are defined by subclassing `nn.Module`.
# The forward method specifies how data flows through the model.
class LSTMModel(nn.Module):
def __init__(self, n_features, n_lookback, n_neurons):
"""
Initialize the LSTM model.
Args:
n_features: Number of input features (e.g., 1 for univariate time series).
n_lookback: Number of past timesteps to consider.
n_neurons: Number of neurons in each LSTM layer.
"""
super(LSTMModel, self).__init__()
self.lstm = nn.LSTM(
input_size=n_features, # Number of input features
hidden_size=n_neurons, # Number of neurons in the LSTM
num_layers=2, # Number of LSTM layers
batch_first=True, # Input shape is (batch, seq, feature)
dropout=0.2, # Dropout for regularization
)
self.fc = nn.Linear(n_neurons, 1) # Fully connected layer for output
def forward(self, x):
"""
Forward pass through the model.
Args:
x: Input tensor of shape (batch, seq_len, n_features).
Returns:
Output tensor of shape (batch, 1).
"""
lstm_out, _ = self.lstm(x) # LSTM outputs (ignore hidden states)
out = self.fc(lstm_out[:, -1, :]) # Use the last timestep's output
return out
# Instantiate the model
n_neurons = 64 # Number of neurons in the LSTM
model = LSTMModel(n_features, n_lookback, n_neurons)
# Step 4: Define Loss Function and Optimizer
# ------------------------------------------
# Loss function: Mean Squared Error (MSE) for regression tasks.
# Optimizer: Adam optimizer for efficient training.
criterion = nn.MSELoss()
optimizer = optim.Adam(model.parameters(), lr=0.0001)
# Step 5: Train the Model
# -----------------------
# PyTorch requires an explicit training loop. This gives you full control
# over the training process.
epochs = 100 # Number of training epochs
# Check for CUDA and set the device
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
print(f"Using device: {device}")
# Move the model to the device
model = LSTMModel(n_features, n_lookback, n_neurons).to(device)
# Move data to the device during training and evaluation
for epoch in range(epochs):
model.train() # Set the model to training mode
train_loss = 0.0
for x_batch, y_batch in train_loader:
# Move data to the device
x_batch = x_batch.to(device)
y_batch = y_batch.to(device)
# Reshape input to (batch, seq_len, n_features)
x_batch = x_batch.view(-1, n_lookback, n_features)
y_batch = y_batch.view(-1, 1)
# Zero the gradients from the previous step
optimizer.zero_grad()
# Forward pass: Compute predictions
predictions = model(x_batch)
# Compute the loss
loss = criterion(predictions, y_batch)
# Backward pass: Compute gradients
loss.backward()
# Update model parameters
optimizer.step()
# Accumulate the loss for reporting
train_loss += loss.item()
# Print epoch loss
print(f"Epoch {epoch+1}/{epochs}, Loss: {train_loss/len(train_loader):.4f}")
if epoch % 10 == 0: # Print every 10 epochs
print(f"Sample prediction: {predictions[0].item()}, Actual: {y_batch[0].item()}")
# Step 6: Evaluate the Model
# --------------------------
# Switch to evaluation mode and disable gradient computation.
model.eval()
with torch.no_grad():
predictions = []
actuals = []
for x_batch, y_batch in test_loader:
# Move data to the device
x_batch = x_batch.to(device)
y_batch = y_batch.to(device)
# Reshape input to (batch, seq_len, n_features)
x_batch = x_batch.view(-1, n_lookback, n_features)
# Make predictions
preds = model(x_batch)
# Move predictions and actuals back to CPU for further processing
predictions.append(preds.cpu().numpy())
actuals.append(y_batch.cpu().numpy())
# Convert predictions and actuals to NumPy arrays for comparison
predictions = np.concatenate(predictions)
actuals = np.concatenate(actuals)
# Step 7: Post-Processing and Visualization
# -----------------------------------------
# Inverse transform the predictions and actuals to get original scale
predictions = scaler.inverse_transform(predictions)
actuals = scaler.inverse_transform(actuals)
# Plot the results
plt.figure(figsize=(20, 5))
plt.plot(actuals, label="Actual")
plt.plot(predictions, label="Predicted")
plt.legend()
plt.show()
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""" this uses new tech
make by conda new -p path python=3.12; conda activate -p path; conda install all those shi
conda install pytorch torchvision torchaudio pytorch-cuda -c pytorch -c nvidia
"""