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i6_setups/hsmm/main.py
2026-01-21 16:30:17 +01:00

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2.5 KiB
Python

import torch
import torch.optim as optim
import matplotlib.pyplot as plt
from hsmm_model import GaussianHSMM
from hsmm_inference import viterbi_decode
from toy_data import generate_toy_data
# --- Settings ---
N_STATES = 10
INPUT_DIM = 5 # Matches the 'dim' in generate_toy_data
MAX_DUR = 50
LR = 0.05
EPOCHS = 20
# In train():
def train():
print("1. Generating Data...")
train_data = generate_toy_data(n_samples=30, seq_len=300, n_clusters=N_STATES, dim=INPUT_DIM)
print("2. Initializing Model...")
model = GaussianHSMM(N_STATES, INPUT_DIM, MAX_DUR)
optimizer = optim.Adam(model.parameters(), lr=LR)
print("3. Training Loop...")
loss_history = []
for epoch in range(EPOCHS):
epoch_loss = 0
optimizer.zero_grad()
# Batching: Gradient Accumulation
for seq in train_data:
loss = model(seq) # Forward pass
loss.backward() # Backward pass
epoch_loss += loss.item()
# Normalize gradients
for p in model.parameters():
if p.grad is not None:
p.grad /= len(train_data)
optimizer.step()
loss_history.append(epoch_loss)
if epoch % 5 == 0:
print(f"Epoch {epoch:02d} | NLL Loss: {epoch_loss:.2f}")
# --- Verification ---
print("\n4. Results:")
learned_means = model.means.detach().view(-1).numpy()
learned_means.sort()
print(f"True Means: [-5.0, 0.0, 5.0]")
print(f"Learned Means: {learned_means}")
# --- Visualization Block in main.py ---
print("5. Visualizing Inference...")
test_seq = train_data[0]
predicted_path = viterbi_decode(model, test_seq)
fig, ax = plt.subplots(2, 1, figsize=(12, 6), sharex=True)
# Plot 1: The Multi-Dimensional Data (Transposed so Time is X-axis)
# This shows the "features" changing color as the state changes
ax[0].imshow(test_seq.numpy().T, aspect='auto', cmap='viridis', interpolation='nearest')
ax[0].set_title(f"Raw Data ({INPUT_DIM} Dimensions)")
ax[0].set_ylabel("Feature Dim")
# Plot 2: The Inferred States
# Reshape path to (1, T) for imshow
path_img = np.array(predicted_path)[np.newaxis, :]
ax[1].imshow(path_img, aspect='auto', cmap='tab10', interpolation='nearest')
ax[1].set_title("Inferred HSMM States")
ax[1].set_ylabel("State ID")
ax[1].set_xlabel("Time (Frames)")
plt.tight_layout()
plt.show()
if __name__ == "__main__":
train()