import  ch.psi.pshell.epics.ChannelDouble as ChannelDouble
A1 = ChannelDouble("x",            "SARUN14-DBPM070:X-REF-FB")
A2 = ChannelDouble("y",            "SARUN14-DBPM070:Y-REF-FB")
S1 = ChannelDouble("hamp",                 "SARFE10-PBPG050:HAMP-INTENSITY")
S2 = ChannelDouble("slow",                 "SARFE10-PBPG050:PHOTON-ENERGY-PER-PULSE-DS")
A1.initialize()
A2.initialize()
S1.initialize()
S2.initialize()
A1_init = A1.read()
A2_init = A2.read()
A1i    = A1_init-0.1
A1f    = A1_init+0.1
A2i    = A2_init-0.1
A2f    = A2_init+0.1
nstep  = 21
lat    = 10.0
nav    = 10
plt    = plot(None, title="Output")[0]
plt.clear()
plt.setStyle(plt.Style.ErrorY)
plt.addSeries(LinePlotErrorSeries("Sensor1", Color.red))

def data_ok():
    return (mps_beam_ok.read() == 1)

def after_sample(record, scan):
    if not data_ok():       
        time.sleep(1.0)
        record.invalidate()    
        print "Invalidating record: " + str(record)
    else:    
        plt.getSeries(0).appendData(record.positions[0], record.readables[0].mean, record.readables[0].stdev)
try:
    S1_averager = create_averager(S1, nav, 0.1)
    S2_averager = create_averager(S2, nav, 0.1)
    S2_averager.monitored=True
    r = ascan((A1,A2), (S1_averager, S2_averager), (A1i,A2i), (A1f,A2f), (nstep,nstep), latency=lat, after_read = after_sample)
    Act1     = r.getPositions(0)
    S1mean   = [val.mean for val in r.getReadable(0)]
    S1rms    = [val.stdev for val in r.getReadable(0)]
    S2mean   = [val.mean for val in r.getReadable(1)]
    S2rmsn   = [val.stdev for val in r.getReadable(1)]
finally:
    A1.write(A1_init)
    A1.close()
    S1.close()
    S2.close()