python compare two date strings with different format - python

Start time is in format datetime with :
YYYY-MM-DDTHH:MM:SS.SSSZ (e.g., 2004-08-04T19:09:02.768Z)
My code
starttime = item['ListingDetails']['StartTime']
present_date = datetime.now() - timedelta(days=2)
startdate = datetime.strptime(starttime, 'WhichFormat')
if startdate.date() < present_date.date():
print('Relisting item :', str(itemid), starttime)
Is throwing the exception because i dont know which was the real format.
Goal is to see if start time is 2 days ago.
I.E If item was relisted 2 days ago + then relist it now

If I understand correctly, you can use dateutil.parser:
import dateutil.parser
starttime = item['ListingDetails']['StartTime']
present_date = datetime.now() - timedelta(days=2)
startdate = dateutil.parser.parse('2004-08-04T19:09:02.768Z')
if startdate.date() < present_date.date():
print('Relisting item :', str(itemid), starttime)

Related

Timestamp conversion and find its difference

I have the following two timestamps
time1 = 2018-05-13 13:06:30
time2 = 2018-05-14T13:49:37.140Z
How to find the difference from it? I am looking for an output that tells the difference in the number of hours in python. The example above case is approx. 23hrs.
Take a look at python datetime model
Anyway, it looks like you have 2 types of string representations of a date, so:
import datetime
time1 = "2018-05-13 13:06:30"
time2 = "2018-05-14T13:49:37.140Z"
time1 = datetime.datetime.strptime(time1, '%Y-%m-%d %H:%M:%S')
time2 = datetime.datetime.strptime(time2, '%Y-%m-%dT%H:%M:%S.%fZ')
print((time2 - time1).total_seconds()/60/60)

I get this error time data '27:07.5' does not match format '%H:%M:%S' (match)

I'm trying to find the difference between the StartTime and LastTime (minutes) in this DataFrame:
StartTime LastTime
1 00:02:05 00:02:05
2 00:07:05 00:07:05
3 00:12:06 00:12:06
4 00:17:06 00:17:06
When I run the following code on the data
from datetime import datetime
date_format = "%H:%M.%S"
# You could also pass datetime.time object in this part and convert it to string.
time_start = str(UDP_interval['StartTime'])
time_end = str(UDP_interval['LastTime'])
# Then get the difference here.
diff = datetime.strptime(time_end, date_format) -
datetime.strptime(time_start, date_format)
# Get the time in hours i.e. 9.60, 8.5
result = diff.seconds / 3600;
I get this error:
dtype: object' does not match format '%H:%M:%S'
You should probably just use:
t_start = list(map(int, str(UDP_interval['StartTime']).split(':'))) # get hours, minutes, seconds separately
t_end = list(map(int, str(UDP_interval['LastTime']).split(':')))
diff = (t_start[0] - t_end[0]) + (t_start[1] - t_start[1]) / 60 + (t_start[2] - t_start[2]) / 3600

Unable to get proper timestamp ranges

I am hoping to generate a range of timestamps between:
18:00 (EST) on October 6th, 2014
and the same time 400 seconds later with an interval size of 2.2 seconds.
Getting the start and end dates:
When I do the following:
start_time = datetime.datetime(year = 2014,
month = 10,
day = 6,
hour = 18,
tzinfo = pytz.timezone('US/Eastern'))
end_time = start_time + datetime.timedelta(seconds=400)
Something seems to fail:
start_time.isoformat() returns '2014-10-06T18:06:40-04:56'
end_time.isoformat() returns '2014-10-06T18:06:40-04:56'
note that the time-zone offset for both timestamps above are: -04:56 (4 hours and 56 minutes) even though EST is 5 hours behind UTC. ?
Getting the time range:
Moving forward, if I try to get a range of timestamps between these two dates every 2.2 seconds (i.e. 2200 ms):
ts = pd.date_range(start=start_time, end=end_time, freq='2200L')
I get:
> ts[0]
Timestamp('2014-10-06 18:56:00-0400', tz='US/Eastern', offset='2200L')
or in other words:
> ts[0].isoformat()
'2014-10-06T18:56:00-04:00'
which also does not make sense (note that the time is 18:56, even though I was asking to get a range between 18:00 and 18:06:40 (i.e. 400 seconds after 18:00)
I got tired of dealing with Python's awkward datetime implementation (particularly with respect to timezones), and have started using crsmithdev.com/arrow. A solution using this lib:
import arrow
start_time = arrow.get(2014, 10, 6, tzinfo='US/Eastern')
end_time = start_time.replace(seconds=400)
print start_time.isoformat()
print end_time.isoformat()
# alternate form
start_time = arrow.get('2014-10-06T18:00:00.000-04:00')
end_time = start_time.replace(seconds=400)
print start_time.isoformat()
print end_time.isoformat()
# get a datetime from an arrow object
start_time_dt = start_time.datetime
import dateutil.parser as parser
import datetime
start_time = parser.parse("06/Oct/2015 18:00 EST")
end_time = start_time + datetime.timedelta(seconds=400)
interval = datetime.timedelta(seconds=2.2)
current_time = start_time
while current_time < end_time:
current_time += interval
print current_time
but I probably dont understand what your issue is

python subtract time and run if loop

I want to compare two times and if the new time is more than 2min then the if statement will print output, I can get the output of datetime.datetime.now() , but how do I check whether the old time is less than 2mins?
#!/usr/bin/env python
import datetime
from time import sleep
now = datetime.datetime.now()
sleep(2)
late = datetime.datetime.now()
constant = 2
diff = late-now
if diff <= constant:
print "True time is less than 2min"
else:
print "Time exceeds 2 mins"
any ideas?
UPDATED:
I am now storing the old date as string in file and then subtract it from current time, the old date is stored in the format
2011-12-16 16:14:50.800856
so when I do
now = "2011-12-16 16:14:50.838638"
sleep(2)
nnow = datetime.strptime(now, '%Y-%m-%d %H:%M:%S')
late = datetime.now()
diff = late-nnow
it gives me this error
ValueError: unconverted data remains: .838638
Subtracting two datetime instances returns a timedelta that has a total_seconds method:
contant = 2 * 60
diff = late-now
if diff.total_seconds() <= constant:
This is only an answer to the update since the answer from sje397 was perfect.
Use a format string like this to match the whole time string:
nnow = datetime.strptime(now, '%Y-%m-%d %H:%M:%S.%f')
The %f matches the microseconds after the dot. This is new since Python 2.6.
You could compare datetime objects by themselves:
from datetime import datetime, timedelta
ts = datetime.strptime("2011-12-16 16:14:50.838638Z", '%Y-%m-%d %H:%M:%S.%fZ')
ts += timedelta(minutes=2) # add 2 minutes
if datetime.utcnow() < ts:
print("time is less")
else:
print("time is more or equal")

How to calculate the time interval between two time strings

I have two times, a start and a stop time, in the format of 10:33:26 (HH:MM:SS). I need the difference between the two times. I've been looking through documentation for Python and searching online and I would imagine it would have something to do with the datetime and/or time modules. I can't get it to work properly and keep finding only how to do this when a date is involved.
Ultimately, I need to calculate the averages of multiple time durations. I got the time differences to work and I'm storing them in a list. I now need to calculate the average. I'm using regular expressions to parse out the original times and then doing the differences.
For the averaging, should I convert to seconds and then average?
Yes, definitely datetime is what you need here. Specifically, the datetime.strptime() method, which parses a string into a datetime object.
from datetime import datetime
s1 = '10:33:26'
s2 = '11:15:49' # for example
FMT = '%H:%M:%S'
tdelta = datetime.strptime(s2, FMT) - datetime.strptime(s1, FMT)
That gets you a timedelta object that contains the difference between the two times. You can do whatever you want with that, e.g. converting it to seconds or adding it to another datetime.
This will return a negative result if the end time is earlier than the start time, for example s1 = 12:00:00 and s2 = 05:00:00. If you want the code to assume the interval crosses midnight in this case (i.e. it should assume the end time is never earlier than the start time), you can add the following lines to the above code:
if tdelta.days < 0:
tdelta = timedelta(
days=0,
seconds=tdelta.seconds,
microseconds=tdelta.microseconds
)
(of course you need to include from datetime import timedelta somewhere). Thanks to J.F. Sebastian for pointing out this use case.
Try this -- it's efficient for timing short-term events. If something takes more than an hour, then the final display probably will want some friendly formatting.
import time
start = time.time()
time.sleep(10) # or do something more productive
done = time.time()
elapsed = done - start
print(elapsed)
The time difference is returned as the number of elapsed seconds.
Here's a solution that supports finding the difference even if the end time is less than the start time (over midnight interval) such as 23:55:00-00:25:00 (a half an hour duration):
#!/usr/bin/env python
from datetime import datetime, time as datetime_time, timedelta
def time_diff(start, end):
if isinstance(start, datetime_time): # convert to datetime
assert isinstance(end, datetime_time)
start, end = [datetime.combine(datetime.min, t) for t in [start, end]]
if start <= end: # e.g., 10:33:26-11:15:49
return end - start
else: # end < start e.g., 23:55:00-00:25:00
end += timedelta(1) # +day
assert end > start
return end - start
for time_range in ['10:33:26-11:15:49', '23:55:00-00:25:00']:
s, e = [datetime.strptime(t, '%H:%M:%S') for t in time_range.split('-')]
print(time_diff(s, e))
assert time_diff(s, e) == time_diff(s.time(), e.time())
Output
0:42:23
0:30:00
time_diff() returns a timedelta object that you can pass (as a part of the sequence) to a mean() function directly e.g.:
#!/usr/bin/env python
from datetime import timedelta
def mean(data, start=timedelta(0)):
"""Find arithmetic average."""
return sum(data, start) / len(data)
data = [timedelta(minutes=42, seconds=23), # 0:42:23
timedelta(minutes=30)] # 0:30:00
print(repr(mean(data)))
# -> datetime.timedelta(0, 2171, 500000) # days, seconds, microseconds
The mean() result is also timedelta() object that you can convert to seconds (td.total_seconds() method (since Python 2.7)), hours (td / timedelta(hours=1) (Python 3)), etc.
This site says to try:
import datetime as dt
start="09:35:23"
end="10:23:00"
start_dt = dt.datetime.strptime(start, '%H:%M:%S')
end_dt = dt.datetime.strptime(end, '%H:%M:%S')
diff = (end_dt - start_dt)
diff.seconds/60
This forum uses time.mktime()
Structure that represent time difference in Python is called timedelta. If you have start_time and end_time as datetime types you can calculate the difference using - operator like:
diff = end_time - start_time
you should do this before converting to particualr string format (eg. before start_time.strftime(...)). In case you have already string representation you need to convert it back to time/datetime by using strptime method.
I like how this guy does it — https://amalgjose.com/2015/02/19/python-code-for-calculating-the-difference-between-two-time-stamps.
Not sure if it has some cons.
But looks neat for me :)
from datetime import datetime
from dateutil.relativedelta import relativedelta
t_a = datetime.now()
t_b = datetime.now()
def diff(t_a, t_b):
t_diff = relativedelta(t_b, t_a) # later/end time comes first!
return '{h}h {m}m {s}s'.format(h=t_diff.hours, m=t_diff.minutes, s=t_diff.seconds)
Regarding to the question you still need to use datetime.strptime() as others said earlier.
Try this
import datetime
import time
start_time = datetime.datetime.now().time().strftime('%H:%M:%S')
time.sleep(5)
end_time = datetime.datetime.now().time().strftime('%H:%M:%S')
total_time=(datetime.datetime.strptime(end_time,'%H:%M:%S') - datetime.datetime.strptime(start_time,'%H:%M:%S'))
print total_time
OUTPUT :
0:00:05
import datetime as dt
from dateutil.relativedelta import relativedelta
start = "09:35:23"
end = "10:23:00"
start_dt = dt.datetime.strptime(start, "%H:%M:%S")
end_dt = dt.datetime.strptime(end, "%H:%M:%S")
timedelta_obj = relativedelta(start_dt, end_dt)
print(
timedelta_obj.years,
timedelta_obj.months,
timedelta_obj.days,
timedelta_obj.hours,
timedelta_obj.minutes,
timedelta_obj.seconds,
)
result:
0 0 0 0 -47 -37
Both time and datetime have a date component.
Normally if you are just dealing with the time part you'd supply a default date. If you are just interested in the difference and know that both times are on the same day then construct a datetime for each with the day set to today and subtract the start from the stop time to get the interval (timedelta).
Take a look at the datetime module and the timedelta objects. You should end up constructing a datetime object for the start and stop times, and when you subtract them, you get a timedelta.
you can use pendulum:
import pendulum
t1 = pendulum.parse("10:33:26")
t2 = pendulum.parse("10:43:36")
period = t2 - t1
print(period.seconds)
would output:
610
import datetime
day = int(input("day[1,2,3,..31]: "))
month = int(input("Month[1,2,3,...12]: "))
year = int(input("year[0~2020]: "))
start_date = datetime.date(year, month, day)
day = int(input("day[1,2,3,..31]: "))
month = int(input("Month[1,2,3,...12]: "))
year = int(input("year[0~2020]: "))
end_date = datetime.date(year, month, day)
time_difference = end_date - start_date
age = time_difference.days
print("Total days: " + str(age))
Concise if you are just interested in the time elapsed that is under 24 hours. You can format the output as needed in the return statement :
import datetime
def elapsed_interval(start,end):
elapsed = end - start
min,secs=divmod(elapsed.days * 86400 + elapsed.seconds, 60)
hour, minutes = divmod(min, 60)
return '%.2d:%.2d:%.2d' % (hour,minutes,secs)
if __name__ == '__main__':
time_start=datetime.datetime.now()
""" do your process """
time_end=datetime.datetime.now()
total_time=elapsed_interval(time_start,time_end)
Usually, you have more than one case to deal with and perhaps have it in a pd.DataFrame(data) format. Then:
import pandas as pd
df['duration'] = pd.to_datetime(df['stop time']) - pd.to_datetime(df['start time'])
gives you the time difference without any manual conversion.
Taken from Convert DataFrame column type from string to datetime.
If you are lazy and do not mind the overhead of pandas, then you could do this even for just one entry.
Here is the code if the string contains days also [-1 day 32:43:02]:
print(
(int(time.replace('-', '').split(' ')[0]) * 24) * 60
+ (int(time.split(' ')[-1].split(':')[0]) * 60)
+ int(time.split(' ')[-1].split(':')[1])
)

Categories