def blocktrans_cen2side(cen_size):
    """ Convert from center rep to side rep
    In center rep, the 6 numbers are center coordinates, then size in 3 dims
    In side rep, the 6 numbers are lower x, y, z, then higher x, y, z """
    cx = float(cen_size[0])
    cy = float(cen_size[1])
    cz = float(cen_size[2])
    sx = float(cen_size[3])
    sy = float(cen_size[4])
    sz = float(cen_size[5])
    lx,ly,lz = cx-sx/2., cy-sy/2., cz-sz/2.
    hx,hy,hz = cx+sx/2., cy+sy/2., cz+sz/2.
    return [lx,ly,lz,hx,hy,hz]