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"""Statistics handling."""
from warnings import warn
from collections import namedtuple
CLOCK_TICK = 320e-9
Stats = namedtuple(
'Stats',
'realtime livetime triggers events icr ocr deadtime')
def stats_from_normal_mode(array):
realtime = float(array[0])
livetime = float(array[1])
triggers = int(array[3])
events = int(array[4])
icr = float(array[5])
ocr = float(array[6])
underflows = int(array[7])
overflows = int(array[8])
total_events = events + underflows + overflows
# Double check the ICR computation
expected_icr = triggers / livetime if livetime != 0 else 0.
if expected_icr != icr:
msg = 'ICR buffer inconsistency: {} != {} (expected)'
warn(msg.format(icr, expected_icr))
# Double check the OCR computation
expected_ocr = total_events / realtime if realtime != 0 else 0.
if expected_ocr != ocr:
msg = 'OCR buffer inconsistency: {} != {} (expected)'
warn(msg.format(ocr, expected_ocr))
# Note that the OCR reported by handel include underflows and overflows,
# while the computed OCR in the returned statistics does not.
return make_stats(realtime, livetime, triggers, events)
def stats_from_mapping_mode(array):
realtime = array[0] * CLOCK_TICK
livetime = array[1] * CLOCK_TICK
triggers = int(array[2])
events = int(array[3])
return make_stats(realtime, livetime, triggers, events)
def make_stats(realtime, livetime, triggers, events):
# ICR/OCR computation
icr = triggers / livetime if livetime != 0 else 0.
ocr = events / realtime if realtime != 0 else 0.
# Deadtime computation
# It's unclear whether icr=ocr=0 should result in a 0.0 or 1.0 deadtime
# Prospect uses 0% so 0. it is.
deadtime = 1 - float(ocr) / icr if icr != 0 else 0.
return Stats(realtime, livetime, triggers, events, icr, ocr, deadtime)
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