Python: how to extend execution time of code to 1 second

Question

I'm writing a countdown clock in python, but it looks like the time module only goes down to the second. Is there a way for me to accurately determine when exactly 1 second has passed?

Seems like my question was a little confusing, let me clarify. I need to run some code, then, at the end, the program enters a while loop and exits once at least 1000 milliseconds have passed since the time the code started running

did you try the datetime module? specifically check out the timedelta object — miraculixx, Dec 02 '16 at 01:51
[Timer](https://docs.python.org/3/library/threading.html#timer-objects) objects. — President James K. Polk, Dec 02 '16 at 01:52
Timer won't really work for what I'm doing, because I need to run some code then wait until the remainder of the second has passed. I don't want to wait a second and then run the code, because then it will be off — user3246167, Dec 02 '16 at 01:54
Remember, precision and accuracy are two different things. Fallenreaper's answer will give you subsecond precision, but I suspect you'll be disappointed in the accuracy. — President James K. Polk, Dec 02 '16 at 02:00

score 1 · Answer 1 · answered Dec 02 '16 at 01:55

Here is a way which will work, though im not sure which modules you are limited to.

import time

def procedure:
    time.sleep(2.5)

# measure wall time
t0 = time.time()
procedure()
print time.time() - t0, "seconds wall time"

2.50023603439 seconds wall time

where procedure is a reference to the function you are timing.

score 1 · Accepted Answer · edited May 23 '17 at 11:45

If you know the code you want to run will take less than 1 second, then 1 - elapsed time will give you the remaining time to sleep, no while loop required.

now = time.time()
foo()
time.sleep(1 - (time.time() - now))

There will be some overhead with the arithmetic, but it's within 1/100 of a second and will be strictly greater than 1 second, as you request. I ran the following code:

import time
import random

def foo():
    time.sleep(random.random())

now = time.time()
foo()
time.sleep(1 - (time.time() - now))

print "Time elapsed: {}".format(time.time() - now)

Output:

Time elapsed: 1.00379300117

You can run this several times to verify it gives the output you want, no matter how long foo takes.

Unless it takes longer than 1 second, then the sleep time will be negative which will result in IOError. You would need to check for that case.

Or, if you need to kill the function if 1 second has passed, check this question

Thanks! exactly what I needed! – user3246167 Dec 02 '16 at 02:18 — user3246167, Dec 02 '16 at 02:18

score -1 · Answer 3 · answered Dec 02 '16 at 01:53

-1

By default the time module gives you the time to the 10^-5 second

import time
time.time()
>>> 1480643510.89443

answered Dec 02 '16 at 01:53

ted

13,596
9
65
107

Python: how to extend execution time of code to 1 second

3 Answers3