如何让python在函数运行时打印出当前经过的时间？

Question

所以我目前有 python 打印一个函数在运行完成后需要多长时间运行，例如：

import time
t = time.time()
# do something in here
print "\n Time Taken: %.3f sec" % (time.time()-t)

但我想显示自函数启动以来已经过去的实时时间，我无法找到一种方法来实现它。

例如在终端中，我希望它说：

Working on xFunction. Time Elapsed 72.485 sec... (live updated time)
xFunction Has finished.
Time Taken: 1152.546 sec

任何帮助将不胜感激。

Answer 1

这是一个带有线程的示例，该线程将打印自启动以来已经过去了多少时间，并且可以从主循环中停止。

import time
import threading

class ElapsedTimeThread(threading.Thread):
    """"Stoppable thread that prints the time elapsed"""
    def __init__(self):
        super(ElapsedTimeThread, self).__init__()
        self._stop_event = threading.Event()

    def stop(self):
        self._stop_event.set()

    def stopped(self):
        return self._stop_event.is_set()

    def run(self):
        thread_start = time.time()
        while not self.stopped():
            print("\rElapsed Time {:.3f} seconds".format(time.time()-thread_start), end="")
            #include a delay here so the thread doesn't uselessly thrash the CPU
            time.sleep(0.01)

if __name__ == "__main__":
    start = time.time()
    thread = ElapsedTimeThread()
    thread.start()
    # do something
    time.sleep(5)
    # something is finished so stop the thread
    thread.stop()
    thread.join()
    print() # empty print() to output a newline
    print("Finished in {:.3f} seconds".format(time.time()-start))

这给出了以下输出，其中Elapsed Time从零开始计数并被覆盖：

J:\>python thr_time.py
Elapsed Time 5.000 seconds
Finished in 5.001 seconds

请注意，此代码在 Python 3 中。有关在此处和此处停止线程的更多信息。

如果您想对任何部分进行澄清，请告诉我。

Answer 2

我修改了 @import_random 的代码，通过包装 2 个用于 ETC 初始化和完成的函数，能够在代码执行期间随时探测经过的时间：

import time
import threading

class ElapsedTimeThread(threading.Thread):
    """"Stoppable thread that prints the time elapsed"""

    
    def __init__(self):
        super(ElapsedTimeThread, self).__init__()
        self._stop_event = threading.Event()
        self.thread_start = time.time()

    def stop(self):
        self._stop_event.set()

    def stopped(self):
        return self._stop_event.is_set()

    def getStart(self):
        return self.thread_start
    
    def getCurrentTime(self):
        print("\rElapsed Time {:.3f} s. ".format(time.time()-self.thread_start), end="", flush=True )
        
    def run(self):
        self.thread_start = time.time()
        while not self.stopped():
            print("\rElapsed Time {:.3f} s. ".format(time.time()-self.thread_start), end="", flush=True)
            #include a delay here so the thread doesn't uselessly thrash the CPU
            time.sleep(0.01)

def startTimeCounter():    
    threadTimer = ElapsedTimeThread()
    threadTimer.start()
    return threadTimer

def stopTimeCounter(threadTimeCounter):
    print() # empty print() to output a newline
    print("Finished in {:.3f} s. ".format(time.time()-threadTimeCounter.getStart()))
    threadTimeCounter.stop()
    threadTimeCounter.join()