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Tracks 3D¶
import numpy as np
import napari
def lissajous(t):
a = np.random.random(size=(3,)) * 80.0 - 40.0
b = np.random.random(size=(3,)) * 0.05
c = np.random.random(size=(3,)) * 0.1
return (a[i] * np.cos(b[i] * t + c[i]) for i in range(3))
def tracks_3d(num_tracks=10):
""" create 3d+t track data """
tracks = []
for track_id in range(num_tracks):
# space to store the track data and features
track = np.zeros((200, 10), dtype=np.float32)
# time
timestamps = np.arange(track.shape[0])
x, y, z = lissajous(timestamps)
track[:, 0] = track_id
track[:, 1] = timestamps
track[:, 2] = 50.0 + z
track[:, 3] = 50.0 + y
track[:, 4] = 50.0 + x
# calculate the speed as a feature
gz = np.gradient(track[:, 2])
gy = np.gradient(track[:, 3])
gx = np.gradient(track[:, 4])
speed = np.sqrt(gx ** 2 + gy ** 2 + gz ** 2)
distance = np.sqrt(x ** 2 + y ** 2 + z ** 2)
track[:, 5] = gz
track[:, 6] = gy
track[:, 7] = gx
track[:, 8] = speed
track[:, 9] = distance
tracks.append(track)
tracks = np.concatenate(tracks, axis=0)
data = tracks[:, :5] # just the coordinate data
features = {
'time': tracks[:, 1],
'gradient_z': tracks[:, 5],
'gradient_y': tracks[:, 6],
'gradient_x': tracks[:, 7],
'speed': tracks[:, 8],
'distance': tracks[:, 9],
}
graph = {}
return data, features, graph
tracks, features, graph = tracks_3d(num_tracks=100)
vertices = tracks[:, 1:]
viewer = napari.Viewer(ndisplay=3)
viewer.add_points(vertices, size=1, name='points', opacity=0.3)
viewer.add_tracks(tracks, features=features, name='tracks')
if __name__ == '__main__':
napari.run()