tivnanmatt's picture
working version
7b1ccbd
# utils.py
import torch
import numpy as np
import matplotlib.pyplot as plt
from gmm import GaussianMixtureModel
def initialize_gmm(mu_list, Sigma_list, pi_list):
mu = torch.tensor(mu_list, dtype=torch.float32)
Sigma = torch.tensor(Sigma_list, dtype=torch.float32)
pi = torch.tensor(pi_list, dtype=torch.float32)
return GaussianMixtureModel(mu, Sigma, pi)
def generate_grid(dx):
x_positions = np.arange(-10, 10.5, 0.5)
y_positions = np.arange(-10, 10.5, 0.5)
fine_points = np.arange(-10, 10 + dx, dx)
ones_same_size = np.ones_like(fine_points)
vertical_lines = [np.stack([x*ones_same_size, fine_points], axis=1) for x in x_positions]
horizontal_lines = [np.stack([fine_points, y*ones_same_size], axis=1) for y in y_positions]
grid_points = np.concatenate(vertical_lines + horizontal_lines, axis=0)
return torch.tensor(grid_points, dtype=torch.float32)
def generate_contours(dtheta):
angles = np.linspace(0, 2 * np.pi, int(2 * np.pi / dtheta))
std_normal_contours = np.concatenate([np.stack([r * np.cos(angles), r * np.sin(angles)], axis=1) for r in range(1, 4)], axis=0)
return torch.tensor(std_normal_contours, dtype=torch.float32)
def transform_std_to_gmm_contours(std_contours, mu, Sigma):
gmm_contours = []
for k in range(mu.shape[0]):
L = torch.linalg.cholesky(Sigma[k])
gmm_contours.append(mu[k] + torch.matmul(std_contours, L.T))
return torch.cat(gmm_contours, dim=0)
def generate_intermediate_points(gmm, grid_points, std_normal_contours, gmm_samples, normal_samples, T, N):
gmm_contours = transform_std_to_gmm_contours(std_normal_contours, gmm.mu.squeeze(), gmm.Sigma)
intermediate_points_gmm_to_normal = gmm.flow_gmm_to_normal(gmm_samples.clone(), T, N)
contour_intermediate_points_gmm_to_normal = gmm.flow_gmm_to_normal(gmm_contours.clone(), T, N)
grid_intermediate_points_gmm_to_normal = gmm.flow_gmm_to_normal(grid_points.clone(), T, N)
intermediate_points_normal_to_gmm = gmm.flow_normal_to_gmm(normal_samples.clone(), T, N)
contour_intermediate_points_normal_to_gmm = gmm.flow_normal_to_gmm(std_normal_contours.clone(), T, N)
grid_intermediate_points_normal_to_gmm = gmm.flow_normal_to_gmm(grid_points.clone(), T, N)
return (intermediate_points_gmm_to_normal, contour_intermediate_points_gmm_to_normal, grid_intermediate_points_gmm_to_normal,
intermediate_points_normal_to_gmm, contour_intermediate_points_normal_to_gmm, grid_intermediate_points_normal_to_gmm)
def plot_samples_and_contours(samples, contours, grid_points, title):
fig, ax = plt.subplots(figsize=(8, 6))
ax.scatter(grid_points[:, 0], grid_points[:, 1], alpha=0.5, c='black', s=1, label='Grid Points')
ax.scatter(contours[:, 0], contours[:, 1], alpha=0.5, s=3, c='blue', label='Contours')
ax.scatter(samples[:, 0], samples[:, 1], alpha=0.5, c='red', label='Samples')
ax.set_title(title)
ax.set_xlabel("x1")
ax.set_ylabel("x2")
ax.grid(True)
ax.legend(loc='upper right')
ax.set_xlim(-5, 5)
ax.set_ylim(-5, 5)
ax.set_aspect('equal', adjustable='box')
plt.close(fig)
return fig, ax