# CvTimer.py
import time
import CvUtil
class Timer:
"""
Stopwatch for timing code execution and logging the results.
timer = CvTimer.Timer('function')
... code to time ...
timer.log()
In a loop, log() will display each iteration's time. Since Timers are started
when created, call reset() before entering the loop or pass in False.
Use logTotal() at the end if you want to see the sum of all iterations.
timer = CvTimer.Timer('draw loop', False)
for/while ...
timer.start()
... code to time ...
timer.log()
timer.logTotal()
A single Timer can be reused for timing loops without creating a new Timer
for each iteration by calling restart().
"""
def __init__(self, item, start=True):
"""Starts the timer."""
self._item = item
self.reset()
if start:
self.start()
def reset(self):
"""Resets all times to zero and stops the timer."""
self._initial = None
self._start = None
self._time = 0
self._total = 0
return self
def start(self):
"""Starts the timer or starts it again if it is already running."""
self._start = time.clock()
if self._initial is None:
self._initial = self._start
return self
def restart(self):
"""Resets all times to zero and starts the timer."""
return self.reset().start()
def stop(self):
"""
Stops the timer if it is running and returns the elapsed time since start,
otherwise returns 0.
"""
if self.running():
self._final = time.clock()
self._time = self._final - self._start
self._total += self._time
self._start = None
return self._time
return 0
def running(self):
"""Returns True if the timer is running."""
return self._start is not None
def time(self):
"""Returns the most recent timing or 0 if none has completed."""
return self._time
def total(self):
"""Returns the sum of all the individual timings."""
return self._total
def span(self):
"""Returns the span of time from the first start() to the last stop()."""
if self._initial is None:
CvUtil.pyPrint("Warning: called span() on a Timer that has not been started")
return 0
elif self._final is None:
return time.clock() - self._initial
else:
return self._final - self._initial
def log(self, extra=None):
"""
Stops the timer and logs the time of the current timing.
This is the same as calling logTotal() or logSpan() for the first time.
"""
self.stop()
return self._log(self.time(), extra)
def logTotal(self, extra="total"):
"""
Stops the timer and logs the sum of all timing steps.
This is the same as calling log() or logSpan() for the first time.
"""
self.stop()
return self._log(self.total(), extra)
def logSpan(self, extra=None):
"""
Stops the timer and logs the span of time covering all timings.
This is the same as calling log() or logTotal() for the first time.
"""
self.stop()
return self._log(self.span(), extra)
def _log(self, runtime, extra):
"""Logs the passed in runtime value."""
if extra is None:
CvUtil.pyPrint("Timer - %s took %d ms" % (self._item, 1000 * runtime))
else:
CvUtil.pyPrint("Timer - %s [%s] took %d ms" % (self._item, str(extra), 1000 * runtime))
return self
