trackpy.motion.imsd¶
- trackpy.motion.imsd(traj, mpp, fps, max_lagtime=100, statistic='msd', pos_columns=None)¶
Compute the mean squared displacement of each particle.
- Parameters:
- trajDataFrame of trajectories of multiple particles, including
columns particle, frame, x, and y
- mppmicrons per pixel
- fpsframes per second
- max_lagtimeintervals of frames out to which MSD is computed
Default: 100
- statistic{‘msd’, ‘<x>’, ‘<y>’, ‘<x^2>’, ‘<y^2>’}, default is ‘msd’
The functions msd() and emsd() return all these as columns. For imsd() you have to pick one.
- Returns:
- DataFrame([Probe 1 msd, Probe 2 msd, …], index=t)
Notes
Input units are pixels and frames. Output units are microns and seconds.