def find_plane_centroid(point_list):
    """
    Function to find centroid given a set of vertices (for patch load). function calculates 2D plane x z - y plane is
    the model plane.
    :param point_list: list of Point() namedtuples
    :type point_list: list
    """
    x = 0
    z = 0
    for point in point_list:
        x += point.x
        z += point.z
    x_c = x / len(point_list)
    z_c = z / len(point_list)
    return [x_c, z_c]