Analyze the flow of points in FlyingThings3D dataset

flyingthings_analysis.py

'''
Finds number of points which do not move for each point cloud in FlyingThings3D dataset.
'''

import numpy as np
import os

root = "./data_processed_maxcut_35_20k_2k_8192"
for file in os.listdir(root):
    if file.endswith(".npz"):
        path = os.path.join(root, file)
        with open(path, 'rb') as fp:
                data = np.load(fp)
                flow = data['flow'].astype('float32')
                stationary = [point for point in flow if np.linalg.norm(point) < 0.001]
                if len(stationary) != 0:
                    print("{} points in {} are stationary.".format(len(stationary), file))