filt.py 文件源码

def traj_diff(t1, t2):
    """Compute trajectory difference.

    Parameters
    ----------
    t1, t2 : DataFrame
        Trajectories.

    Returns
    -------
    diff : DataFrame
        Trajectory difference. It can be interpreted as errors in `t1` relative
        to `t2`.
    """
    diff = t1 - t2
    diff['lat'] *= np.deg2rad(earth.R0)
    diff['lon'] *= np.deg2rad(earth.R0) * np.cos(0.5 *
                                                 np.deg2rad(t1.lat + t2.lat))
    diff['h'] %= 360
    diff.h[diff.h < -180] += 360
    diff.h[diff.h > 180] -= 360

    return diff.loc[t1.index.intersection(t2.index)]