expt_utils.py 文件源码

def _cart2polar(x, y):
    """
    Transform Cartesian coordinates to polar

    Parameters
    ----------
    x, y : floats or arrays
        Cartesian coordinates

    Returns
    -------
    r, theta : floats or arrays
        Polar coordinates

    """
    r = np.sqrt(x**2 + y**2)
    theta = np.arctan2(x, y)  # ? referenced to vertical
    return r, theta