def METHOD_NAME(self, xyz_size, xyz_dim, stack=True):
    """helper for ``read_input_c3d``"""
    xmin, xmax, ymin, ymax, zmin, zmax = xyz_size
    xdim, ydim, zdim = xyz_dim
    x = linspace(0., 1., num=xdim)
    y = linspace(0., 1., num=ydim)
    z = linspace(0., 1., num=zdim)
    self.log.debug(str(x))
    # organized in x, y, z planes order
    planes = (
        # yz
        # xmin, xmax
        ((xmin, ymin, zmin), (xmin, ymin, zmax), (xmin, ymax, zmax), (xmin, ymax, zmin), y, z),
        ((xmax, ymin, zmin), (xmax, ymin, zmax), (xmax, ymax, zmax), (xmax, ymax, zmin), y, z), # wrong
        ## xz
        # ymin, ymax
        ((xmin, ymin, zmin), (xmin, ymin, zmax), (xmax, ymin, zmax), (xmax, ymin, zmin), x, z),
        ((xmin, ymax, zmin), (xmin, ymax, zmax), (xmax, ymax, zmax), (xmax, ymax, zmin), x, z),
        # xy
        # zmin, zmax
        ((xmin, ymin, zmin), (xmin, ymax, zmin), (xmax, ymax, zmin), (xmax, ymin, zmin), x, y),
        ((xmin, ymin, zmax), (xmin, ymax, zmax), (xmax, ymax, zmax), (xmax, ymin, zmax), x, y),
    )
    points = []
    elements = []
    nnodes = 0
    for plane in planes:
        p1, p2, p3, p4, xi, yi = plane
        p1 = array(p1, dtype='float32')
        p2 = array(p2, dtype='float32')
        p3 = array(p3, dtype='float32')
        p4 = array(p4, dtype='float32')
        self.log.debug(str(plane[:1]))
        pointsi, elementsi = points_elements_from_quad_points(p1, p2, p3, p4, xi, yi)
        points.append(pointsi)
        if stack:
            elements.append(elementsi + nnodes)
            nnodes += pointsi.shape[0]
        else:
            elements.append(elementsi)
        #break
        #print(points)
    if stack:
        points = vstack(points)
        elements = vstack(elements)
    return points, elements