sit2standpy.v2.get_stillness

sit2standpy.v2.utility.get_stillness(filt_accel, dt, window, gravity, thresholds)

Stillness determination based on filtered acceleration magnitude and jerk magnitude

Parameters:

filt_accel : numpy.ndarray

1D array of filtered magnitude of acceleration data, units of m/s^2

dt : float

Sampling time, in seconds

window : float

Moving statistics window length, in seconds

gravity : float

Gravitational acceleration, as measured by the sensor during static periods.

thresholds : dict

Dictionary of the 4 thresholds to be used - accel moving avg, accel moving std, jerk moving avg, and jerk moving std. Acceleration average thresholds should be for difference from gravitional acceleration.

Returns:

still : numpy.ndarray

(N, ) boolean array of stillness (True)

starts : numpy.ndarray

(Q, ) array of indices where stillness starts. Includes index 0 if still[0] is True. Q < (N/2)

stops : numpy.ndarray

(Q, ) array of indices where stillness ends. Includes index N-1 if still[-1] is True. Q < (N/2)