def set_pol_cplus(offset = None, timeout = -1):
    """
    """
    print "Set x-ray polarization to c+"
    timeout = int(timeout *1000) if timeout>0 else timeout
    pol_mode.write("CIRC +")
    if offset is not None:
        pol_offset.write(float(offset))
    time.sleep(0.5)
    pol_done.update()
    pol_done.waitValue("DONE",timeout) 
    print "Done setting x-ray polarization"   

def set_pol_cminus(offset = None, timeout = -1):
    """
    """
    print "Set x-ray polarizaton to c-"
    timeout = int(timeout *1000) if timeout>0 else timeout
    pol_mode.write("CIRC -")
    if offset is not None:
        pol_offset.write(float(offset))
    time.sleep(0.5)
    pol_done.update()
    pol_done.waitValue("DONE",timeout)   
    print "Done setting x-ray polarization"