我正在编写一个时钟对象，可用于计算程序中的事件，然后报告其不同的时间，例如它运行的时间，开始和停止时间等。我还写了一个 clocks 对象，它跟踪整个程序中使用的各种时钟实例，并总结打印输出中所有时钟的详细信息。
我已经有了时钟对象，但是我很难看到如何在当前的实现中跟踪它的开始时间。这是因为它会重置其开始时间的内部记录，以便正确地为其内部累加器添加时间。我很感激任何关于让事情发挥作用的指导。
代码如下。我已经将代码包含在 clocks 对象等等，以便明确我想要实现的内容，以便建议的解决方案不会删除关键功能（我已将其设为最小的我知道怎么回事。）
from __future__ import division
import os
import time
import uuid as uuid
import datetime
def main():
global clocks
clocks = Clocks()
print("create clock alpha")
alpha = Clock(name = "alpha")
print("clock alpha start time: {time}".format(time = alpha.startTime()))
print("sleep 2 seconds")
time.sleep(2)
print("clock alpha current time (s): {time}".format(time = alpha.time()))
print
print("create clock beta")
beta = Clock(name = "beta")
print("clock beta start time: {time}".format(time = beta.startTime()))
print("sleep 2 seconds")
time.sleep(2)
print("clock beta current time (s): {time}".format(time = beta.time()))
print("stop clock beta")
beta.stop()
print("clock beta start time: {time}".format(time = beta.startTime()))
print("clock beta stop time: {time}".format(time = beta.stopTime()))
print("sleep 2 seconds")
time.sleep(2)
print("clock beta current time (s): {time}".format(time = beta.time()))
print
print("create two gamma clocks")
gamma1 = Clock(name = "gamma")
gamma1 = Clock(name = "gamma")
print("sleep 2 seconds")
time.sleep(2)
print
print("create two unnamed clocks")
delta = Clock()
epsilon = Clock()
print("sleep 2 seconds")
time.sleep(2)
print
print("clocks full printout:\n")
clocks.printout(style = "full")
print("clocks statistics printout:\n")
clocks.printout()
class Clock(object):
def __init__(
self,
name = None,
start = True
):
self._name = name
self._start = start # Boolean start clock on instantiation
self._updateTime = None # internal
# If no name is specified, generate a unique one.
if self._name is None:
self._name = UID()
# If a global clock list is detected, add a clock instance to it.
if "clocks" in globals():
clocks.add(self)
self.reset()
if self._start:
self.start()
def start(self):
self._startTime = datetime.datetime.utcnow()
def stop(self):
self._updateTime = None
self._startTime = None
self._stopTime = datetime.datetime.utcnow()
# Update the clock accumulator.
def update(self):
if self._updateTime:
self.accumulator += (
datetime.datetime.utcnow() - self._updateTime
)
else:
self.accumulator += (
datetime.datetime.utcnow() - self._startTime
)
self._updateTime = datetime.datetime.utcnow()
def reset(self):
self.accumulator = datetime.timedelta(0)
self._startTime = None
# If the clock has a start time, add the difference between now and the
# start time to the accumulator and return the accumulation. If the clock
# does not have a start time, return the accumulation.
def elapsed(self):
if self._startTime:
self.update()
return(self.accumulator)
def name(
self
):
return(self._name)
def time(self):
return(self.elapsed().total_seconds())
def startTime(self):
if self._startTime:
return(style_datetime_object(datetimeObject = self._startTime))
else:
return("none")
def stopTime(self):
if self._stopTime:
return(style_datetime_object(datetimeObject = self._stopTime))
else:
return("none")
class Clocks(object):
def __init__(
self
):
self._listOfClocks = []
self._defaultReportStyle = "statistics"
def add(
self,
clock
):
self._listOfClocks.append(clock)
def report(
self,
style = None
):
if style is None:
style = self._defaultReportStyle
if self._listOfClocks != []:
if style == "statistics":
# Create a dictionary of clock types with corresponding lists of
# times for all instances.
dictionaryOfClockTypes = {}
# Get the names of all clocks and add them to the dictionary.
for clock in self._listOfClocks:
dictionaryOfClockTypes[clock.name()] = []
# Record the values of all clocks for their respective names in
# the dictionary.
for clock in self._listOfClocks:
dictionaryOfClockTypes[clock.name()].append(clock.time())
# Create a report, calculating the average value for each clock
# type.
string = "clock type".ljust(39) + "mean time (s)"
for name, values in dictionaryOfClockTypes.iteritems():
string += "\n" +\
str(name).ljust(39) + str(sum(values)/len(values))
string += "\n"
elif style == "full":
# Create a report, listing the values of all clocks.
string = "clock".ljust(39) + "time (s)"
for clock in self._listOfClocks:
string += "\n" +\
str(clock.name()).ljust(39) + str(clock.time())
string += "\n"
else:
string = "no clocks"
return(string)
def printout(
self,
style = None
):
if style is None:
style = self._defaultReportStyle
print(self.report(style = style))
def UID():
return(str(uuid.uuid4()))
def style_datetime_object(
datetimeObject = None,
style = "YYYY-MM-DDTHHMMSS"
):
# filename safe
if style == "YYYY-MM-DDTHHMMSSZ":
return(datetimeObject.strftime('%Y-%m-%dT%H%M%SZ'))
# microseconds
elif style == "YYYY-MM-DDTHHMMSSMMMMMMZ":
return(datetimeObject.strftime('%Y-%m-%dT%H%M%S%fZ'))
# elegant
elif style == "YYYY-MM-DD HH:MM:SS UTC":
return(datetimeObject.strftime('%Y-%m-%d %H:%M:%SZ'))
# UNIX time in seconds with second fraction
elif style == "UNIX time S.SSSSSS":
return(
(datetimeObject -\
datetime.datetime.utcfromtimestamp(0)).total_seconds()
)
# UNIX time in seconds rounded
elif style == "UNIX time S":
return(
int((datetimeObject -\
datetime.datetime.utcfromtimestamp(0)).total_seconds())
)
# filename safe
else:
return(datetimeObject.strftime('%Y-%m-%dT%H%M%SZ'))
if __name__ == '__main__':
main()
运行时的打印输出示例如下：
create clock alpha
clock alpha start time: 2014-12-28T060943Z
sleep 2 seconds
clock alpha current time (s): 2.001554
create clock beta
clock beta start time: 2014-12-28T060945Z
sleep 2 seconds
clock beta current time (s): 2.001759
stop clock beta
clock beta start time: none
clock beta stop time: 2014-12-28T060947Z
sleep 2 seconds
clock beta current time (s): 2.001759
create two gamma clocks
sleep 2 seconds
create two unnamed clocks
sleep 2 seconds
clocks full printout:
clock time (s)
alpha 10.01031
beta 2.001759
gamma 4.004501
gamma 4.004482
fdce3cc9-2178-4a72-99c5-22c77ad9cbbc 2.002209
d90d9263-ffaf-44f1-ace9-f8ddf5c78d87 2.002156
clocks statistics printout:
clock type mean time (s)
alpha 10.010368
beta 2.001759
d90d9263-ffaf-44f1-ace9-f8ddf5c78d87 2.00219
gamma 4.004532
fdce3cc9-2178-4a72-99c5-22c77ad9cbbc 2.002244
说明问题的关键是clock beta start time: none。时钟“beta”应该在此时报告2014-12-28T060945Z。
答案 0 :(得分：1)
你的问题（我认为，我没有阅读你的整个代码）是在这个块的开头：
print("create clock beta")
beta = Clock(name = "beta")
print("clock beta start time: {time}".format(time = beta.startTime()))
print("sleep 2 seconds")
time.sleep(2)
print("clock beta current time (s): {time}".format(time = beta.time()))
print("stop clock beta")
beta.stop()
print("clock beta start time: {time}".format(time = beta.stopTime())) # right here
print("clock beta stop time: {time}".format(time = beta.stopTime()))
print("sleep 2 seconds")
time.sleep(2)
print("clock beta current time (s): {time}".format(time = beta.time()))
您正在打印“时钟测试版开始时间：”，但您将beta.stopTime()的结果传递给字符串格式化程序，就像您在下一行中所做的一样。另外，既然你打电话给beta.stop()，我不确定你对最后一行的期望是什么，理论上beta在2秒前被停止了。