Im using datetime with pytz, but i cant get time to update.
format = "[%B %d %H:%M]"
now_utc = datetime.now(timezone('UTC'))
greece = now_utc.astimezone(timezone('Europe/Athens'))
date = greece.strftime(format)
For example i print(date) at 11:30, it stays like that.
Any idea?
As it is, date remains the same throughout the runtime. There is nothing to update it at the current time. If you want to check and print the time at regular intervals, you need to define a function and have your script call it after that amount of time.
import time
fmt = "[%B %d %H:%M]"
def print_now()
now_utc = datetime.now(timezone('UTC'))
greece = now_utc.astimezone(timezone('Europe/Athens'))
date = greece.strftime(fmt)
print(date)
while True:
print_now()
time.sleep(60) # argument is time to wait in seconds
As long as True is True (which is always), the loop will continue, unless you define some condition to force it to end at some point. Of course, you could have the print_now() function contents within the while loop, but it's a bit cleaner to have it in it's own function.
if (time.clock() > 10:
DO SOMETHING
this only works with 1 iteration of the function then the time.clock surpasses 10seconds.
How do I do:
if (time.clock > time.clock + 10):
how do I save a value for the clock at a particular instance??
I have already tried the get_time() function although this doesn't work on the account that python throws an attribute error
You can save time.clock in a variable
first_instance = time.clock()
if (time.clock > first_instance + 10):
you could rather do
import time
time.sleep(10)
#do something.
You could also use the modulus operator
if(time.clock() % 10 == 0)
#do something
But this will make something happen after every 10th second, and also at the 0th second. But the benefit would be being able to change the behavior to work every 11th second for example which maybe would be preferable or every 12th second. For example every 15th second would be:
if(time.clock() % 15 == 0)
#do something
I'm trying to get a for loop to print the value of 'i' every 5 minutes
import threading
def f(i):
print(i)
threading.Timer(600, f).start()
for i in range(1,1000000000000):
f(i=i)
However, this method results in the code printing the value of i instantly since it calls 'f' as soon as it finds 'i'.
I know this is not the first time someone will ask, nor the last, but I can't get it to work on a for loop nested within a function.
I'm fairly new to Python and I'd appreciate any help.
How about just keeping track of how long has passed in the loop?
from timeit import default_timer as timer
start = timer()
freq = 5 * 60 # Time in seconds
last_time = 0.0
for i in range(int(1e8)):
ctime = timer()
if ctime - last_time > freq:
print(i)
last_time = ctime
I imagine you can make this more efficient by only checking the time every N iterations rather than every time. You may also want to look into using progressbar2 for a ready-made solution.
I prefer using datetime, as I think it's more intuitive and looks a bit cleaner. Otherwise, using more or less the same approach as Paul:
from datetime import datetime, timedelta
print_interval = timedelta(minutes=5)
# Initialize the next print time. Using now() will print the first
# iteration and then every interval. To avoid printing the first
# time, just add print_interval here (i.e. uncomment).
next_print = datetime.now() # + print_interval
for i in range(int(1e8)):
now = datetime.now()
if now >= next_print:
next_print = now + print_interval
print(i)
Also note that before python 3.x xrange would be preferable over range.
I want to make my function trigger at 0 second,30second every minute.
Rather than use time.sleep(30) because the script will run for months and have some blocking system call,
I want to make it happens on specific time like 12:00:00, 12:00:30, 12:01:00
How could I do it on Python 2.7
Not sure how your function works but if there is any sort of a loop you could use an if statement.
t = time.time()
while/for loop:
...
if time.time() > t + 30:
yourFunction()
t = time.time()
...
EDIT:
My fault, misread that. Similar method but you can use date time, probably better off looking into chrontab though. This method is a little hacky and if your script is small and can cycle every second this will work, otherwise go chrontab.
import datetime
t = datetime.datetime
run = True
while/for loop:
...
if t.now().second % 30 == 0 and run == True:
yourFunction()
run = False
if t.now().second % 30 == 1:
run = True
...
I know that I can cause a thread to sleep for a specific amount of time with:
time.sleep(NUM)
How can I make a thread sleep until 2AM? Do I have to do math to determine the number of seconds until 2AM? Or is there some library function?
( Yes, I know about cron and equivalent systems in Windows, but I want to sleep my thread in python proper and not rely on external stimulus or process signals.)
Here's a half-ass solution that doesn't account for clock jitter or adjustment of the clock. See comments for ways to get rid of that.
import time
import datetime
# if for some reason this script is still running
# after a year, we'll stop after 365 days
for i in xrange(0,365):
# sleep until 2AM
t = datetime.datetime.today()
future = datetime.datetime(t.year,t.month,t.day,2,0)
if t.hour >= 2:
future += datetime.timedelta(days=1)
time.sleep((future-t).total_seconds())
# do 2AM stuff
You can use the pause package, and specifically the pause.until function, for this:
import pause
from datetime import datetime
pause.until(datetime(2015, 8, 12, 2))
Slightly more generalized solution (based off of Ross Rogers') in case you'd like to add minutes as well.
def sleepUntil(self, hour, minute):
t = datetime.datetime.today()
future = datetime.datetime(t.year, t.month, t.day, hour, minute)
if t.timestamp() > future.timestamp():
future += datetime.timedelta(days=1)
time.sleep((future-t).total_seconds())
Another approach, using sleep, decreasing the timeout logarithmically.
def wait_until(end_datetime):
while True:
diff = (end_datetime - datetime.now()).total_seconds()
if diff < 0: return # In case end_datetime was in past to begin with
time.sleep(diff/2)
if diff <= 0.1: return
Building on the answer of #MZA and the comment of #Mads Y
One possible approach is to sleep for an hour. Every hour, check if the time is in the middle of the night. If so, proceed with your operation. If not, sleep for another hour and continue.
If the user were to change their clock in the middle of the day, this approach would reflect that change. While it requires slightly more resources, it should be negligible.
I tried the "pause" pacakage. It does not work for Python 3.x. From the pause package I extracted the code required to wait until a specific datetime and made the following def.
def wait_until(execute_it_now):
while True:
diff = (execute_it_now - datetime.now()).total_seconds()
if diff <= 0:
return
elif diff <= 0.1:
time.sleep(0.001)
elif diff <= 0.5:
time.sleep(0.01)
elif diff <= 1.5:
time.sleep(0.1)
else:
time.sleep(1)
adapt this:
from datetime import datetime, timedelta
from time import sleep
now = datetime.utcnow
to = (now() + timedelta(days = 1)).replace(hour=1, minute=0, second=0)
sleep((to-now()).seconds)
Slightly beside the point of the original question:
Even if you don't want to muck around with crontabs, if you can schedule python scripts to those hosts, you might be interested to schedule anacron tasks? anacron's major differentiator to cron is that it does not rely the computer to run continuously. Depending on system configuration you may need admin rights even for such user-scheduled tasks.
A similar, more modern tool is upstart provided by the Ubuntu folks: http://upstart.ubuntu.com/
This does not yet even have the required features. But scheduling jobs and replacing anacron is a planned feature. It has quite some traction due to its usage as Ubuntu default initd replacement. (I am not affiliated with the project)
Of course, with the already provided answer, you can code the same functionality into your python script and it might suit you better in your case.
Still, for others, anacron or similar existing systems might be a better solution. anacron is preinstalled on many current linux distributions (there are portability issues for windows users).
Wikipedia provides a pointer page: https://en.wikipedia.org/wiki/Anacron
If you do go for a python version I'd look at the asynchronous aspect, and ensure the script works even if the time is changed (daylight savings, etc) as others have commented already. Instead of waiting til a pre-calculated future, I'd always at maximum wait one hour, then re-check the time. The compute cycles invested should be negligible even on mobile, embedded systems.
Asynchronous version of Omrii's solution
import datetime
import asyncio
async def sleep_until(hour: int, minute: int, second: int):
"""Asynchronous wait until specific hour, minute and second
Args:
hour (int): Hour
minute (int): Minute
second (int): Second
"""
t = datetime.datetime.today()
future = datetime.datetime(t.year, t.month, t.day, hour, minute, second)
if t.timestamp() > future.timestamp():
future += datetime.timedelta(days=1)
await asyncio.sleep((future - t).total_seconds())
I know is way late for this, but I wanted to post an answer (inspired on the marked answer) considering systems that might have - incorrect - desired timezone + include how to do this threaded for people wondering how.
It looks big because I'm commenting every step to explain the logic.
import pytz #timezone lib
import datetime
import time
from threading import Thread
# using this as I am, check list of timezone strings at:
## https://en.wikipedia.org/wiki/List_of_tz_database_time_zones
TIMEZONE = pytz.timezone("America/Sao_Paulo")
# function to return desired seconds, even if it's the next day
## check the bkp_time variable (I use this for a bkp thread)
## to edit what time you want to execute your thread
def get_waiting_time_till_two(TIMEZONE):
# get current time and date as our timezone
## later we remove the timezone info just to be sure no errors
now = datetime.datetime.now(tz=TIMEZONE).replace(tzinfo=None)
curr_time = now.time()
curr_date = now.date()
# Make 23h30 string into datetime, adding the same date as current time above
bkp_time = datetime.datetime.strptime("02:00:00","%H:%M:%S").time()
bkp_datetime = datetime.datetime.combine(curr_date, bkp_time)
# extract the difference from both dates and a day in seconds
bkp_minus_curr_seconds = (bkp_datetime - now).total_seconds()
a_day_in_seconds = 60 * 60 * 24
# if the difference is a negative value, we will subtract (- with + = -)
# it from a day in seconds, otherwise it's just the difference
# this means that if the time is the next day, it will adjust accordingly
wait_time = a_day_in_seconds + bkp_minus_curr_seconds if bkp_minus_curr_seconds < 0 else bkp_minus_curr_seconds
return wait_time
# Here will be the function we will call at threading
def function_we_will_thread():
# this will make it infinite during the threading
while True:
seconds = get_waiting_time_till_two(TIMEZONE)
time.sleep(seconds)
# Do your routine
# Now this is the part where it will be threading
thread_auto_update = Thread(target=function_we_will_thread)
thread_auto_update.start()
It takes only one of the very basic libraries.
import time
sleep_until = 'Mon Dec 25 06:00:00 2020' # String format might be locale dependent.
print("Sleeping until {}...".format(sleep_until))
time.sleep(time.mktime(time.strptime(sleep_until)) - time.time())
time.strptime() parses the time from string -> struct_time tuple. The string can be in different format, if you give strptime() parse-format string as a second argument. E.g.
time.strptime("12/25/2020 02:00AM", "%m/%d/%Y %I:%M%p")
time.mktime() turns the struct_time -> epoch time in seconds.
time.time() gives current epoch time in seconds.
Substract the latter from the former and you get the wanted sleep time in seconds.
sleep() the amount.
If you just want to sleep until whatever happens to be the next 2AM, (might be today or tomorrow), you need an if-statement to check if the time has already passed today. And if it has, set the wake up for the next day instead.
import time
sleep_until = "02:00AM" # Sets the time to sleep until.
sleep_until = time.strftime("%m/%d/%Y " + sleep_until, time.localtime()) # Adds todays date to the string sleep_until.
now_epoch = time.time() #Current time in seconds from the epoch time.
alarm_epoch = time.mktime(time.strptime(sleep_until, "%m/%d/%Y %I:%M%p")) # Sleep_until time in seconds from the epoch time.
if now_epoch > alarm_epoch: #If we are already past the alarm time today.
alarm_epoch = alarm_epoch + 86400 # Adds a day worth of seconds to the alarm_epoch, hence setting it to next day instead.
time.sleep(alarm_epoch - now_epoch) # Sleeps until the next time the time is the set time, whether it's today or tomorrow.
What about this handy and simple solution?
from datetime import datetime
import time
pause_until = datetime.fromisoformat('2023-02-11T00:02:00') # or whatever timestamp you gonna need
time.sleep((pause_until - datetime.now()).total_seconds())
from datetime import datetime
import time, operator
time.sleep([i[0]*3600 + i[1]*60 for i in [[H, M]]][0] - [i[0]*3600 + i[1]*60 for i in [map(int, datetime.now().strftime("%H:%M").split(':'))]][0])
Instead of using the wait() function, you can use a while-loop checking if the specified date has been reached yet:
if datetime.datetime.utcnow() > next_friday_10am:
# run thread or whatever action
next_friday_10am = next_friday_10am()
time.sleep(30)
def next_friday_10am():
for i in range(7):
for j in range(24):
for k in range(60):
if (datetime.datetime.utcnow() + datetime.timedelta(days=i)).weekday() == 4:
if (datetime.datetime.utcnow() + datetime.timedelta(days=i, hours=j)).hour == 8:
if (datetime.datetime.utcnow() + datetime.timedelta(days=i, hours=j, minutes=k)).minute == 0:
return datetime.datetime.utcnow() + datetime.timedelta(days=i, hours=j, minutes=k)
Still has the time-checking thread check the condition every after 30 seconds so there is more computing required than in waiting, but it's a way to make it work.