plot/plot_mppi.py

import numpy as np
import matplotlib.pyplot as plt
import argparse
import os
import glob

def load_data(log_path):
    """Load data from npz file"""
    data = np.load(log_path)
    return {
        'states': data['states'],
        'targets': data['targets'],
        'costs': data['costs'],
        'times': data['times'],
        'actions': data['actions']
    }

def plot_ball_trajectory(times, states, save_path):
    """Plot ball z-axis trajectory"""
    ball_z = states[:, 0, 0] if states.ndim == 3 else states[:, 0]
    
    plt.figure(figsize=(10, 6))
    plt.plot(times, ball_z, 'b-', linewidth=2, label='Ball Z Position')
    plt.xlabel('Time (s)')
    plt.ylabel('Z Position (m)')
    plt.title('Ball Trajectory')
    plt.grid(True, alpha=0.3)
    plt.legend()
    plt.tight_layout()
    plt.savefig(f"{save_path}/ball_trajectory.png", dpi=300)
    plt.close()

def plot_reference_trajectory(times, targets, save_path):
    """Plot reference z-axis trajectory"""
    ref_z = targets[:, 2] if targets.ndim == 2 else targets[:, 0, 2]
    
    plt.figure(figsize=(10, 6))
    plt.plot(times, ref_z, 'r--', linewidth=2, label='Reference Z Position')
    plt.xlabel('Time (s)')
    plt.ylabel('Z Position (m)')
    plt.title('Reference Trajectory')
    plt.grid(True, alpha=0.3)
    plt.legend()
    plt.tight_layout()
    plt.savefig(f"{save_path}/reference_trajectory.png", dpi=300)
    plt.close()

def plot_cost(times, costs, save_path):
    """Plot cost over time"""
    plt.figure(figsize=(10, 6))
    plt.plot(times, costs, 'g-', linewidth=2, label='Cost')
    plt.xlabel('Time (s)')
    plt.ylabel('Cost')
    plt.title('Cost Over Time')
    plt.grid(True, alpha=0.3)
    plt.legend()
    plt.tight_layout()
    plt.savefig(f"{save_path}/cost.png", dpi=300)
    plt.close()

def plot_actions(times, actions, save_path):
    """Plot actions over time"""
    plt.figure(figsize=(10, 6))
    plt.plot(times, actions, 'm-', linewidth=2, label='Action')
    plt.xlabel('Time (s)')
    plt.ylabel('Action Value')
    plt.title('Actions Over Time')
    plt.grid(True, alpha=0.3)
    plt.legend()
    plt.tight_layout()
    plt.savefig(f"{save_path}/actions.png", dpi=300)
    plt.close()

def plot_comparison(times, states, targets, save_path):
    """Plot ball and reference trajectories together"""
    ball_z = states[:, 0, 0] if states.ndim == 3 else states[:, 0]
    ref_z = targets[:, 2] if targets.ndim == 2 else targets[:, 0, 2]
    
    plt.figure(figsize=(12, 6))
    plt.plot(times, ball_z, 'b-', linewidth=2, label='Ball Z Position')
    plt.plot(times, ref_z, 'r--', linewidth=2, label='Reference Z Position')
    plt.xlabel('Time (s)')
    plt.ylabel('Z Position (m)')
    plt.title('Ball vs Reference Trajectory')
    plt.grid(True, alpha=0.3)
    plt.legend()
    plt.tight_layout()
    plt.savefig(f"{save_path}/comparison.png", dpi=300)
    plt.close()

def main():
    parser = argparse.ArgumentParser(description='Plot MPPI tracking results')
    parser.add_argument('--log_dir',default='/home/lau/sim/DynaTraj/logs/bb/20250924_143716', type=str, help='Path to log directory')
    args = parser.parse_args()
    
    # Find npz file
    npz_files = glob.glob(os.path.join(args.log_dir, "*.npz"))
    if not npz_files:
        print(f"No npz files found in {args.log_dir}")
        return
    
    npz_file = npz_files[0]
    print(f"Loading data from {npz_file}")
    
    # Load data
    data = load_data(npz_file)
    times = data['times']
    states = data['states']
    targets = data['targets']
    costs = data['costs']
    actions = data['actions']
    
    # Create plots
    print("Generating plots...")
    plot_ball_trajectory(times, states, args.log_dir)
    plot_reference_trajectory(times, targets, args.log_dir)
    plot_cost(times, costs, args.log_dir)
    plot_actions(times, actions, args.log_dir)
    plot_comparison(times, states, targets, args.log_dir)
    
    print(f"Plots saved to {args.log_dir}")

if __name__ == "__main__":
    main()