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FakeISISEventDAE v1

../_images/FakeISISEventDAE-v1_dlg.png

FakeISISEventDAE dialog.

Summary

Simulates ISIS event DAE.

See Also

FakeISISHistoDAE

Properties

Name

Direction

Type

Default

Description

NPeriods

Input

number

1

Number of periods.

NSpectra

Input

number

100

Number of spectra.

Rate

Input

number

20

Rate of sending the data: stream of NEvents events is sent every Rate milliseconds.

NEvents

Input

number

1000

Number of events in each packet.

Port

Input

number

59876

The port to broadcast on (default 59876, ISISDAE 10000).

Description

Simulates ISIS event DAE. It runs continuously until canceled and listens to port 10000 for connection. When connected starts sending event packets.

Events are randomly distributed between the following

  • Periods

  • Spectra

  • time of flight between 10,000 and 20,000

Usage

Example:

from threading import Thread
import time

def startFakeDAE():
    # This will generate 2000 events roughly every 20ms, so about 50,000 events/sec
    # They will be randomly shared across the 100 spectra
    # and have a time of flight between 10,000 and 20,000
    try:
        FakeISISEventDAE(NPeriods=1,NSpectra=100,Rate=20,NEvents=1000)
    except RuntimeError:
        pass

def captureLive():
    ConfigService.setFacility("TEST_LIVE")

    try:
        # start a Live data listener updating every second, that rebins the data
        # and replaces the results each time with those of the last second.
        StartLiveData(Instrument='ISIS_Event', OutputWorkspace='wsOut', UpdateEvery=1,
                      ProcessingAlgorithm='Rebin', ProcessingProperties='Params=10000,1000,20000;PreserveEvents=1',
                      AccumulationMethod='Add', PreserveEvents=True)

        # give it a couple of seconds before stopping it
        time.sleep(2)
    finally:
        # This will cancel both algorithms
        # you can do the same in the GUI
        # by clicking on the details button on the bottom right
        AlgorithmManager.cancelAll()
        time.sleep(1)
#--------------------------------------------------------------------------------------------------

oldFacility = ConfigService.getFacility().name()
thread = Thread(target = startFakeDAE)
thread.start()
time.sleep(2) # give it a small amount of time to get ready
if not thread.is_alive():
    raise RuntimeError("Unable to start FakeDAE")

try:
    captureLive()
except:
    print("Error occurred starting live data")
finally:
    thread.join() # this must get hit

# put back the facility
ConfigService.setFacility(oldFacility)

#get the output workspace
wsOut = mtd["wsOut"]
print("The workspace contains %i events" % wsOut.getNumberEvents())

Output:

 The workspace contains ... events

Categories: AlgorithmIndex | DataHandling\DataAcquisition

Source

C++ header: FakeISISEventDAE.h

C++ source: FakeISISEventDAE.cpp