I've never had to convert time to and from UTC. Recently had a request to have my app be timezone aware, and I've been running myself in circles. Lots of information on converting local time to UTC, which I found fairly elementary (maybe I'm doing that wrong as well), but I can not find any information on easily converting the UTC time to the end-users timezone.
In a nutshell, and android app sends me (appengine app) data and within that data is a timestamp. To store that timestamp to utc time I am using:
datetime.utcfromtimestamp(timestamp)
That seems to be working. When my app stores the data, it is being store as 5 hours ahead (I am EST -5)
The data is being stored on appengine's BigTable, and when retrieved it comes out as a string like so:
"2011-01-21 02:37:21"
How do I convert this string to a DateTime in the users correct time zone?
Also, what is the recommended storage for a users timezone information? (How do you typically store tz info ie: "-5:00" or "EST" etc etc ?) I'm sure the answer to my first question might contain a parameter the answers the second.
If you don't want to provide your own tzinfo objects, check out the python-dateutil library. It provides tzinfo implementations on top of a zoneinfo (Olson) database such that you can refer to time zone rules by a somewhat canonical name.
from datetime import datetime
from dateutil import tz
# METHOD 1: Hardcode zones:
from_zone = tz.gettz('UTC')
to_zone = tz.gettz('America/New_York')
# METHOD 2: Auto-detect zones:
from_zone = tz.tzutc()
to_zone = tz.tzlocal()
# utc = datetime.utcnow()
utc = datetime.strptime('2011-01-21 02:37:21', '%Y-%m-%d %H:%M:%S')
# Tell the datetime object that it's in UTC time zone since
# datetime objects are 'naive' by default
utc = utc.replace(tzinfo=from_zone)
# Convert time zone
central = utc.astimezone(to_zone)
Edit Expanded example to show strptime usage
Edit 2 Fixed API usage to show better entry point method
Edit 3 Included auto-detect methods for timezones (Yarin)
Here's a resilient method that doesn't depend on any external libraries:
from datetime import datetime
import time
def datetime_from_utc_to_local(utc_datetime):
now_timestamp = time.time()
offset = datetime.fromtimestamp(now_timestamp) - datetime.utcfromtimestamp(now_timestamp)
return utc_datetime + offset
This avoids the timing issues in DelboyJay's example. And the lesser timing issues in Erik van Oosten's amendment.
As an interesting footnote, the timezone offset computed above can differ from the following seemingly equivalent expression, probably due to daylight savings rule changes:
offset = datetime.fromtimestamp(0) - datetime.utcfromtimestamp(0) # NO!
Update: This snippet has the weakness of using the UTC offset of the present time, which may differ from the UTC offset of the input datetime. See comments on this answer for another solution.
To get around the different times, grab the epoch time from the time passed in. Here's what I do:
def utc2local(utc):
epoch = time.mktime(utc.timetuple())
offset = datetime.fromtimestamp(epoch) - datetime.utcfromtimestamp(epoch)
return utc + offset
See the datetime documentation on tzinfo objects. You have to implement the timezones you want to support yourself. The are examples at the bottom of the documentation.
Here's a simple example:
from datetime import datetime,tzinfo,timedelta
class Zone(tzinfo):
def __init__(self,offset,isdst,name):
self.offset = offset
self.isdst = isdst
self.name = name
def utcoffset(self, dt):
return timedelta(hours=self.offset) + self.dst(dt)
def dst(self, dt):
return timedelta(hours=1) if self.isdst else timedelta(0)
def tzname(self,dt):
return self.name
GMT = Zone(0,False,'GMT')
EST = Zone(-5,False,'EST')
print datetime.utcnow().strftime('%m/%d/%Y %H:%M:%S %Z')
print datetime.now(GMT).strftime('%m/%d/%Y %H:%M:%S %Z')
print datetime.now(EST).strftime('%m/%d/%Y %H:%M:%S %Z')
t = datetime.strptime('2011-01-21 02:37:21','%Y-%m-%d %H:%M:%S')
t = t.replace(tzinfo=GMT)
print t
print t.astimezone(EST)
Output
01/22/2011 21:52:09
01/22/2011 21:52:09 GMT
01/22/2011 16:52:09 EST
2011-01-21 02:37:21+00:00
2011-01-20 21:37:21-05:00a
If you want to get the correct result even for the time that corresponds to an ambiguous local time (e.g., during a DST transition) and/or the local utc offset is different at different times in your local time zone then use pytz timezones:
#!/usr/bin/env python
from datetime import datetime
import pytz # $ pip install pytz
import tzlocal # $ pip install tzlocal
local_timezone = tzlocal.get_localzone() # get pytz tzinfo
utc_time = datetime.strptime("2011-01-21 02:37:21", "%Y-%m-%d %H:%M:%S")
local_time = utc_time.replace(tzinfo=pytz.utc).astimezone(local_timezone)
This answer should be helpful if you don't want to use any other modules besides datetime.
datetime.utcfromtimestamp(timestamp) returns a naive datetime object (not an aware one). Aware ones are timezone aware, and naive are not. You want an aware one if you want to convert between timezones (e.g. between UTC and local time).
If you aren't the one instantiating the date to start with, but you can still create a naive datetime object in UTC time, you might want to try this Python 3.x code to convert it:
import datetime
d=datetime.datetime.strptime("2011-01-21 02:37:21", "%Y-%m-%d %H:%M:%S") #Get your naive datetime object
d=d.replace(tzinfo=datetime.timezone.utc) #Convert it to an aware datetime object in UTC time.
d=d.astimezone() #Convert it to your local timezone (still aware)
print(d.strftime("%d %b %Y (%I:%M:%S:%f %p) %Z")) #Print it with a directive of choice
Be careful not to mistakenly assume that if your timezone is currently MDT that daylight savings doesn't work with the above code since it prints MST. You'll note that if you change the month to August, it'll print MDT.
Another easy way to get an aware datetime object (also in Python 3.x) is to create it with a timezone specified to start with. Here's an example, using UTC:
import datetime, sys
aware_utc_dt_obj=datetime.datetime.now(datetime.timezone.utc) #create an aware datetime object
dt_obj_local=aware_utc_dt_obj.astimezone() #convert it to local time
#The following section is just code for a directive I made that I liked.
if sys.platform=="win32":
directive="%#d %b %Y (%#I:%M:%S:%f %p) %Z"
else:
directive="%-d %b %Y (%-I:%M:%S:%f %p) %Z"
print(dt_obj_local.strftime(directive))
If you use Python 2.x, you'll probably have to subclass datetime.tzinfo and use that to help you create an aware datetime object, since datetime.timezone doesn't exist in Python 2.x.
If using Django, you can use the timezone.localtime method:
from django.utils import timezone
date
# datetime.datetime(2014, 8, 1, 20, 15, 0, 513000, tzinfo=<UTC>)
timezone.localtime(date)
# datetime.datetime(2014, 8, 1, 16, 15, 0, 513000, tzinfo=<DstTzInfo 'America/New_York' EDT-1 day, 20:00:00 DST>)
The following worked for me in a Cloud environment for US west:
import datetime
import pytz
#set the timezone
tzInfo = pytz.timezone('America/Los_Angeles')
dt = datetime.datetime.now(tz=tzInfo)
print(dt)
Consolidating the answer from franksands into a convenient method.
import calendar
import datetime
def to_local_datetime(utc_dt):
"""
convert from utc datetime to a locally aware datetime according to the host timezone
:param utc_dt: utc datetime
:return: local timezone datetime
"""
return datetime.datetime.fromtimestamp(calendar.timegm(utc_dt.timetuple()))
You can use arrow
from datetime import datetime
import arrow
now = datetime.utcnow()
print(arrow.get(now).to('local').format())
# '2018-04-04 15:59:24+02:00'
you can feed arrow.get() with anything. timestamp, iso string etc
You can use calendar.timegm to convert your time to seconds since Unix epoch and time.localtime to convert back:
import calendar
import time
time_tuple = time.strptime("2011-01-21 02:37:21", "%Y-%m-%d %H:%M:%S")
t = calendar.timegm(time_tuple)
print time.ctime(t)
Gives Fri Jan 21 05:37:21 2011 (because I'm in UTC+03:00 timezone).
import datetime
def utc_str_to_local_str(utc_str: str, utc_format: str, local_format: str):
"""
:param utc_str: UTC time string
:param utc_format: format of UTC time string
:param local_format: format of local time string
:return: local time string
"""
temp1 = datetime.datetime.strptime(utc_str, utc_format)
temp2 = temp1.replace(tzinfo=datetime.timezone.utc)
local_time = temp2.astimezone()
return local_time.strftime(local_format)
utc_tz_example_str = '2018-10-17T00:00:00.111Z'
utc_fmt = '%Y-%m-%dT%H:%M:%S.%fZ'
local_fmt = '%Y-%m-%dT%H:%M:%S+08:00'
# call my function here
local_tz_str = utc_str_to_local_str(utc_tz_example_str, utc_fmt, local_fmt)
print(local_tz_str) # 2018-10-17T08:00:00+08:00
When I input utc_tz_example_str = 2018-10-17T00:00:00.111Z, （UTC +00:00）
then I will get local_tz_str = 2018-10-17T08:00:00+08:00 （My target timezone +08:00）
parameter utc_format is a format determined by your specific utc_tz_example_str.
parameter local_fmt is the final desired format.
In my case, my desired format is %Y-%m-%dT%H:%M:%S+08:00 ( +08:00 timezone). You should construct the format you want.
This worked for me:
from django.utils import timezone
from datetime import timedelta,datetime
ist_time = timezone.now() + timedelta(hours=5,minutes=30)
#second method
ist_time = datetime.now() + timedelta(hours=5,minutes=30)
I traditionally defer this to the frontend -- send times from the backend as timestamps or some other datetime format in UTC, then let the client figure out the timezone offset and render this data in the proper timezone.
For a webapp, this is pretty easy to do in javascript -- you can figure out the browser's timezone offset pretty easily using builtin methods and then render the data from the backend properly.
From the answer here, you can use the time module to convert from utc to the local time set in your computer:
utc_time = time.strptime("2018-12-13T10:32:00.000", "%Y-%m-%dT%H:%M:%S.%f")
utc_seconds = calendar.timegm(utc_time)
local_time = time.localtime(utc_seconds)
Here is a quick and dirty version that uses the local systems settings to work out the time difference. NOTE: This will not work if you need to convert to a timezone that your current system is not running in. I have tested this with UK settings under BST timezone
from datetime import datetime
def ConvertP4DateTimeToLocal(timestampValue):
assert isinstance(timestampValue, int)
# get the UTC time from the timestamp integer value.
d = datetime.utcfromtimestamp( timestampValue )
# calculate time difference from utcnow and the local system time reported by OS
offset = datetime.now() - datetime.utcnow()
# Add offset to UTC time and return it
return d + offset
Short and simple:
from datetime import datetime
t = "2011-01-21 02:37:21"
datetime.fromisoformat(t) + (datetime.now() - datetime.utcnow())
Related
I know these questions have been asked before but I'm struggling to convert a timestamp string to a unix time and figuring out whether the datetime objects are naive or aware
For example, to convert the time "2021-05-19 12:51:47" to unix:
>>> from datetime import datetime as dt
>>> dt_obj = dt.strptime("2021-05-19 12:51:47", "%Y-%m-%d %H:%M:%S")
>>> dt_obj
datetime.datetime(2021, 5, 19, 12, 51, 47)
is dt_obj naive or aware and how would you determine this? The methods on dt_obj such as timetz, tzinfo, and tzname don't seem to indicate anything - does that mean that dt_obj is naive?
Then to get unix:
>>> dt_obj.timestamp()
1621421507.0
However when I check 1621421507.0 on say https://www.unixtimestamp.com then it tells me that gmt for the above is Wed May 19 2021 10:51:47 GMT+0000, ie 2 hours behind the original timestamp?
since Python's datetime treats naive datetime as local time by default, you need to set the time zone (tzinfo attribute):
from datetime import datetime, timezone
# assuming "2021-05-19 12:51:47" represents UTC:
dt_obj = datetime.fromisoformat("2021-05-19 12:51:47").replace(tzinfo=timezone.utc)
Or, as #Wolf suggested, instead of setting the tzinfo attribute explicitly, you can also modify the input string by adding "+00:00" which is parsed to UTC;
dt_obj = datetime.fromisoformat("2021-05-19 12:51:47" + "+00:00")
In any case, the result
dt_obj.timestamp()
# 1621428707.0
now converts as expected on https://www.unixtimestamp.com/:
As long as you don't specify the timezone when calling strptime, you will produce naive datetime objects. You may pass time zone information via %z format specifier and +00:00 added to the textual date-time representation to get a timezone aware datetime object:
from datetime import datetime
dt_str = "2021-05-19 12:51:47"
print(dt_str)
dt_obj = datetime.strptime(dt_str+"+00:00", "%Y-%m-%d %H:%M:%S%z")
print(dt_obj)
print(dt_obj.timestamp())
The of above script is this:
2021-05-19 12:51:47
2021-05-19 12:51:47+00:00
1621428707.0
datetime.timestamp()
Naive datetime instances are assumed to represent local time and this method relies on the platform C mktime() function to perform the conversion.
So using this does automatically apply yours machine current timezone, following recipe is given to calculate timestamp from naive datetime without influence of timezone:
timestamp = (dt - datetime(1970, 1, 1)) / timedelta(seconds=1)
I would like to convert string date format to timestamp with microseconds
I try the following but not giving expected result:
"""input string date -> 2014-08-01 04:41:52,117
expected result -> 1410748201.117"""
import time
import datetime
myDate = "2014-08-01 04:41:52,117"
timestamp = time.mktime(datetime.datetime.strptime(myDate, "%Y-%m-%d %H:%M:%S,%f").timetuple())
print timestamp
> 1410748201.0
Where did the milliseconds go?
There is no slot for the microseconds component in a time tuple:
>>> import time
>>> import datetime
>>> myDate = "2014-08-01 04:41:52,117"
>>> datetime.datetime.strptime(myDate, "%Y-%m-%d %H:%M:%S,%f").timetuple()
time.struct_time(tm_year=2014, tm_mon=8, tm_mday=1, tm_hour=4, tm_min=41, tm_sec=52, tm_wday=4, tm_yday=213, tm_isdst=-1)
You'll have to add those manually:
>>> dt = datetime.datetime.strptime(myDate, "%Y-%m-%d %H:%M:%S,%f")
>>> time.mktime(dt.timetuple()) + (dt.microsecond / 1000000.0)
1406864512.117
The other method you could follow is to produce a timedelta() object relative to the epoch, then get the timestamp with the timedelta.total_seconds() method:
epoch = datetime.datetime.fromtimestamp(0)
(dt - epoch).total_seconds()
The use of a local time epoch is quite deliberate since you have a naive (not timezone-aware) datetime value. This method can be inaccurate based on the history of your local timezone however, see J.F. Sebastian's comment. You'd have to convert the naive datetime value to a timezone-aware datetime value first using your local timezone before subtracting a timezone-aware epoch.
As such, it is easier to stick to the timetuple() + microseconds approach.
Demo:
>>> dt = datetime.datetime.strptime(myDate, "%Y-%m-%d %H:%M:%S,%f")
>>> epoch = datetime.datetime.fromtimestamp(0)
>>> (dt - epoch).total_seconds()
1406864512.117
In Python 3.4 and later you can use
timestamp = datetime.datetime.strptime(myDate, "%Y-%m-%d %H:%M:%S,%f").timestamp()
This doesn't require importing the time module. It also uses less steps so it should be faster. For older versions of python the other provided answers are probably your best option.
However, the resulting timestamp will interpret myDate in local time, rather than UTC, which may cause issues if myDate was given in UTC
Where did the milliseconds go?
It is the easy part. .timetuple() call drops them. You could add them back using .microsecond attribute. The datetime.timestamp() method from the standard library works that way for naive datetime objects:
def timestamp(self):
"Return POSIX timestamp as float"
if self._tzinfo is None:
return _time.mktime((self.year, self.month, self.day,
self.hour, self.minute, self.second,
-1, -1, -1)) + self.microsecond / 1e6
else:
return (self - _EPOCH).total_seconds()
It is enough if possible ~1 hour errors could be ignored in your case. I assume that you want microseconds and therefore you can't ignore ~1 hour time errors silently.
To convert the local time given as a string to the POSIX timestamp correctly is a complex task in general. You could convert the local time to UTC and then get the timestamp from UTC time.
There are two main issues:
local time may be non-existent or ambiguous e.g. during DST transitions the same time may occur twice
UTC offset for the local timezone may be different in the past and therefore a naive: local time minus epoch in local time formula may fail
Both can be solved using the tz database (pytz module in Python):
from datetime import datetime
import pytz # $ pip install pytz
from tzlocal import get_localzone # $ pip install tzlocal
tz = get_localzone() # get pytz timezone corresponding to the local timezone
naive_d = datetime.strptime(myDate, "%Y-%m-%d %H:%M:%S,%f")
# a) raise exception for non-existent or ambiguous times
d = tz.localize(naive_d, is_dst=None)
## b) assume standard time, adjust non-existent times
#d = tz.normalize(tz.localize(naive_d, is_dst=False))
## c) assume DST is in effect, adjust non-existent times
#d = tz.normalize(tz.localize(naive_d, is_dst=True))
timestamp = d - datetime(1970, 1, 1, tzinfo=pytz.utc)
The result is timestamp -- a timedelta object, you can convert it to seconds, milliseconds, etc.
Also different systems may behave differently around/during leap seconds. Most application can ignore that they exist.
In general, it might be simpler to store POSIX timestamps in addition to the local time instead of trying to guess it from the local time.
I have dt = datetime(2013,9,1,11), and I would like to get a Unix timestamp of this datetime object.
When I do (dt - datetime(1970,1,1)).total_seconds() I got the timestamp 1378033200.
When converting it back using datetime.fromtimestamp I got datetime.datetime(2013, 9, 1, 6, 0).
The hour doesn't match. What did I miss here?
solution is
import time
import datetime
d = datetime.date(2015,1,5)
unixtime = time.mktime(d.timetuple())
If you want to convert a python datetime to seconds since epoch you should do it explicitly:
>>> import datetime
>>> datetime.datetime(2012, 04, 01, 0, 0).strftime('%s')
'1333234800'
>>> (datetime.datetime(2012, 04, 01, 0, 0) - datetime.datetime(1970, 1, 1)).total_seconds()
1333238400.0
In Python 3.3+ you can use timestamp() instead:
>>> import datetime
>>> datetime.datetime(2012, 4, 1, 0, 0).timestamp()
1333234800.0
What you missed here is timezones.
Presumably you've five hours off UTC, so 2013-09-01T11:00:00 local and 2013-09-01T06:00:00Z are the same time.
You need to read the top of the datetime docs, which explain about timezones and "naive" and "aware" objects.
If your original naive datetime was UTC, the way to recover it is to use utcfromtimestamp instead of fromtimestamp.
On the other hand, if your original naive datetime was local, you shouldn't have subtracted a UTC timestamp from it in the first place; use datetime.fromtimestamp(0) instead.
Or, if you had an aware datetime object, you need to either use a local (aware) epoch on both sides, or explicitly convert to and from UTC.
If you have, or can upgrade to, Python 3.3 or later, you can avoid all of these problems by just using the timestamp method instead of trying to figure out how to do it yourself. And even if you don't, you may want to consider borrowing its source code.
(And if you can wait for Python 3.4, it looks like PEP 341 is likely to make it into the final release, which means all of the stuff J.F. Sebastian and I were talking about in the comments should be doable with just the stdlib, and working the same way on both Unix and Windows.)
Rather than this expression to create a POSIX timestamp from dt,
(dt - datetime(1970,1,1)).total_seconds()
Use this:
int(dt.strftime("%s"))
I get the right answer in your example using the second method.
EDIT: Some followup... After some comments (see below), I was curious about the lack of support or documentation for %s in strftime. Here's what I found:
In the Python source for datetime and time, the string STRFTIME_FORMAT_CODES tells us:
"Other codes may be available on your platform.
See documentation for the C library strftime function."
So now if we man strftime (on BSD systems such as Mac OS X), you'll find support for %s:
"%s is replaced by the number of seconds since the Epoch, UTC (see mktime(3))."
Anyways, that's why %s works on the systems it does. But there are better solutions to OP's problem (that take timezones into account). See #abarnert's accepted answer here.
For working with UTC timezones:
time_stamp = calendar.timegm(dt.timetuple())
datetime.utcfromtimestamp(time_stamp)
You've missed the time zone info (already answered, agreed)
arrow package allows to avoid this torture with datetimes; It is already written, tested, pypi-published, cross-python (2.6 — 3.xx).
All you need: pip install arrow (or add to dependencies)
Solution for your case
dt = datetime(2013,9,1,11)
arrow.get(dt).timestamp
# >>> 1378033200
bc = arrow.get(1378033200).datetime
print(bc)
# >>> datetime.datetime(2013, 9, 1, 11, 0, tzinfo=tzutc())
print(bc.isoformat())
# >>> '2013-09-01T11:00:00+00:00'
If your datetime object represents UTC time, don't use time.mktime, as it assumes the tuple is in your local timezone. Instead, use calendar.timegm:
>>> import datetime, calendar
>>> d = datetime.datetime(1970, 1, 1, 0, 1, 0)
>>> calendar.timegm(d.timetuple())
60
def dt2ts(dt, utc=False):
if utc:
return calendar.timegm(dt.timetuple())
if dt.tzinfo is None:
return int(time.mktime(dt.timetuple()))
utc_dt = dt.astimezone(tz.tzutc()).timetuple()
return calendar.timegm(utc_dt)
If you want UTC timestamp :time.mktime just for local dt .Use calendar.timegm is safe but dt must the utc zone so change the zone to utc. If dt in UTC just use calendar.timegm.
def datetime_to_epoch(d1):
"""
January 1st, 1970 at 00:00:00 UTC is referred to as the Unix epoch
:param d1: input date
:return: seconds since unix epoch
"""
if not d1.tzinfo:
raise ValueError("date is missing timezone information")
d2 = datetime(1970, 1, 1, tzinfo=timezone.utc)
time_delta = d1 - d2
ts = int(time_delta.total_seconds())
return ts
def epoch_to_datetime_string(timestamp, tz_name="UTC", **kwargs):
"""
method to convert unix timestamp to date time string
:param ts: 10 digit unix timestamp in seconds
:param tz_name: timezone name
:param kwargs: formatter=<formatter-string>
:return: date time string in timezone
"""
naive_date = datetime.fromtimestamp(timestamp)
aware_date = naive_date.astimezone(pytz.timezone(tz_name))
formatter = kwargs.pop("formatter", "%d %b %Y %H:%M:%S")
return aware_date.strftime(formatter)
Well, when converting TO unix timestamp, python is basically assuming UTC, but while converting back it will give you a date converted to your local timezone.
See this question/answer;
Get timezone used by datetime.datetime.fromtimestamp()
This class will cover your needs, you can pass the variable into ConvertUnixToDatetime & call which function you want it to operate based off.
from datetime import datetime
import time
class ConvertUnixToDatetime:
def __init__(self, date):
self.date = date
# Convert unix to date object
def convert_unix(self):
unix = self.date
# Check if unix is a string or int & proceeds with correct conversion
if type(unix).__name__ == 'str':
unix = int(unix[0:10])
else:
unix = int(str(unix)[0:10])
date = datetime.utcfromtimestamp(unix).strftime('%Y-%m-%d %H:%M:%S')
return date
# Convert date to unix object
def convert_date(self):
date = self.date
# Check if datetime object or raise ValueError
if type(date).__name__ == 'datetime':
unixtime = int(time.mktime(date.timetuple()))
else:
raise ValueError('You are trying to pass a None Datetime object')
return type(unixtime).__name__, unixtime
if __name__ == '__main__':
# Test Date
date_test = ConvertUnixToDatetime(datetime.today())
date_test = date_test.convert_date()
print(date_test)
# Test Unix
unix_test = ConvertUnixToDatetime(date_test[1])
print(unix_test.convert_unix())
import time
from datetime import datetime
time.mktime(datetime.now().timetuple())
Im working on converting epoch timestamps to dates in different timezones with pytz. What I am trying to do is create a DateTime object that accepts an Olson database timezone and an epoch time and returns a localized datetime object. Eventually I need to answer questions like "What hour was it in New York at epoch time 1350663248?"
Something is not working correctly here:
import datetime, pytz, time
class DateTime:
def __init__(self, timezone, epoch):
self.timezone = timezone
self.epoch = epoch
timezoneobject = pytz.timezone(timezone)
datetimeobject = datetime.datetime.fromtimestamp( self.epoch )
self.datetime = timezoneobject.localize(datetimeobject)
def hour(self):
return self.datetime.hour
if __name__=='__main__':
epoch = time.time()
dt = DateTime('America/Los_Angeles',epoch)
print dt.datetime.hour
dt = DateTime('America/New_York',epoch)
print dt.datetime.hour
This prints the same hour, whereas one should be 3 or so hours ahead. Whats going wrong here? I'm a total Python beginner, any help is appreciated!
datetime.fromtimestamp(self.epoch) returns localtime that shouldn't be used with an arbitrary timezone.localize(); you need utcfromtimestamp() to get datetime in UTC and then convert it to a desired timezone:
from datetime import datetime
import pytz
# get time in UTC
utc_dt = datetime.utcfromtimestamp(posix_timestamp).replace(tzinfo=pytz.utc)
# convert it to tz
tz = pytz.timezone('America/New_York')
dt = utc_dt.astimezone(tz)
# print it
print(dt.strftime('%Y-%m-%d %H:%M:%S %Z%z'))
Or a simpler alternative is to construct from the timestamp directly:
from datetime import datetime
import pytz
# get time in tz
tz = pytz.timezone('America/New_York')
dt = datetime.fromtimestamp(posix_timestamp, tz)
# print it
print(dt.strftime('%Y-%m-%d %H:%M:%S %Z%z'))
It converts from UTC implicitly in this case.
For creating the datetime object belonging to particular timezone from a unix timestamp, you may pass the pytz object as a tz parameter while creating your datetime. For example:
>>> from datetime import datetime
>>> import pytz
>>> datetime.fromtimestamp(1350663248, tz= pytz.timezone('America/New_York'))
datetime.datetime(2012, 10, 19, 12, 14, 8, tzinfo=<DstTzInfo 'America/New_York' EDT-1 day, 20:00:00 DST>)
You can get the list of all timezones using pytz.all_timezones which returns exhaustive list of the timezone names that can be used.
Also take a look at List of tz database time zones wiki.
epochdt = datetime.datetime.fromtimestamp(epoch)
timezone1 = timezone("Timezone/String")
adjusted_datetime = timezone1.localize(epochdt)
Working from memory, so excuse any syntax errors, but that should get you on the right track.
EDIT: Missed the part about knowing the hour,etc. Python has great Time/Date Formatting. At pretty much the bottom of that link is the table showing how to pull different attributes from the datetime object.
I have a string representing a unix timestamp (i.e. "1284101485") in Python, and I'd like to convert it to a readable date. When I use time.strftime, I get a TypeError:
>>>import time
>>>print time.strftime("%B %d %Y", "1284101485")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: argument must be 9-item sequence, not str
Use datetime module:
from datetime import datetime
ts = int('1284101485')
# if you encounter a "year is out of range" error the timestamp
# may be in milliseconds, try `ts /= 1000` in that case
print(datetime.utcfromtimestamp(ts).strftime('%Y-%m-%d %H:%M:%S'))
>>> from datetime import datetime
>>> datetime.fromtimestamp(1172969203.1)
datetime.datetime(2007, 3, 4, 0, 46, 43, 100000)
Taken from http://seehuhn.de/pages/pdate
The most voted answer suggests using fromtimestamp which is error prone since it uses the local timezone. To avoid issues a better approach is to use UTC:
datetime.datetime.utcfromtimestamp(posix_time).strftime('%Y-%m-%dT%H:%M:%SZ')
Where posix_time is the Posix epoch time you want to convert
>>> import time
>>> time.ctime(int("1284101485"))
'Fri Sep 10 16:51:25 2010'
>>> time.strftime("%D %H:%M", time.localtime(int("1284101485")))
'09/10/10 16:51'
There are two parts:
Convert the unix timestamp ("seconds since epoch") to the local time
Display the local time in the desired format.
A portable way to get the local time that works even if the local time zone had a different utc offset in the past and python has no access to the tz database is to use a pytz timezone:
#!/usr/bin/env python
from datetime import datetime
import tzlocal # $ pip install tzlocal
unix_timestamp = float("1284101485")
local_timezone = tzlocal.get_localzone() # get pytz timezone
local_time = datetime.fromtimestamp(unix_timestamp, local_timezone)
To display it, you could use any time format that is supported by your system e.g.:
print(local_time.strftime("%Y-%m-%d %H:%M:%S.%f%z (%Z)"))
print(local_time.strftime("%B %d %Y")) # print date in your format
If you do not need a local time, to get a readable UTC time instead:
utc_time = datetime.utcfromtimestamp(unix_timestamp)
print(utc_time.strftime("%Y-%m-%d %H:%M:%S.%f+00:00 (UTC)"))
If you don't care about the timezone issues that might affect what date is returned or if python has access to the tz database on your system:
local_time = datetime.fromtimestamp(unix_timestamp)
print(local_time.strftime("%Y-%m-%d %H:%M:%S.%f"))
On Python 3, you could get a timezone-aware datetime using only stdlib (the UTC offset may be wrong if python has no access to the tz database on your system e.g., on Windows):
#!/usr/bin/env python3
from datetime import datetime, timezone
utc_time = datetime.fromtimestamp(unix_timestamp, timezone.utc)
local_time = utc_time.astimezone()
print(local_time.strftime("%Y-%m-%d %H:%M:%S.%f%z (%Z)"))
Functions from the time module are thin wrappers around the corresponding C API and therefore they may be less portable than the corresponding datetime methods otherwise you could use them too:
#!/usr/bin/env python
import time
unix_timestamp = int("1284101485")
utc_time = time.gmtime(unix_timestamp)
local_time = time.localtime(unix_timestamp)
print(time.strftime("%Y-%m-%d %H:%M:%S", local_time))
print(time.strftime("%Y-%m-%d %H:%M:%S+00:00 (UTC)", utc_time))
In Python 3.6+:
import datetime
timestamp = 1642445213
value = datetime.datetime.fromtimestamp(timestamp)
print(f"{value:%Y-%m-%d %H:%M:%S}")
Output (local time)
2022-01-17 20:46:53
Explanation
Line #1: Import datetime library.
Line #2: Unix time which is seconds since 1970-01-01.
Line #3: Converts this to a unix time object, check with: type(value)
Line #4: Prints in the same format as strp. Local time. To print in UTC see example below.
Bonus
To save the date to a string then print it, use this:
my_date = f"{value:%Y-%m-%d %H:%M:%S}"
print(my_date)
To output in UTC:
value = datetime.datetime.fromtimestamp(timestamp, tz=datetime.timezone.utc)
# 2022-01-17 18:50:52
Other than using time/datetime package, pandas can also be used to solve the same problem.Here is how we can use pandas to convert timestamp to readable date:
Timestamps can be in two formats:
13 digits(milliseconds) -
To convert milliseconds to date, use:
import pandas
result_ms=pandas.to_datetime('1493530261000',unit='ms')
str(result_ms)
Output: '2017-04-30 05:31:01'
10 digits(seconds) -
To convert seconds to date, use:
import pandas
result_s=pandas.to_datetime('1493530261',unit='s')
str(result_s)
Output: '2017-04-30 05:31:01'
For a human readable timestamp from a UNIX timestamp, I have used this in scripts before:
import os, datetime
datetime.datetime.fromtimestamp(float(os.path.getmtime("FILE"))).strftime("%B %d, %Y")
Output:
'December 26, 2012'
You can convert the current time like this
t=datetime.fromtimestamp(time.time())
t.strftime('%Y-%m-%d')
'2012-03-07'
To convert a date in string to different formats.
import datetime,time
def createDateObject(str_date,strFormat="%Y-%m-%d"):
timeStamp = time.mktime(time.strptime(str_date,strFormat))
return datetime.datetime.fromtimestamp(timeStamp)
def FormatDate(objectDate,strFormat="%Y-%m-%d"):
return objectDate.strftime(strFormat)
Usage
=====
o=createDateObject('2013-03-03')
print FormatDate(o,'%d-%m-%Y')
Output 03-03-2013
timestamp ="124542124"
value = datetime.datetime.fromtimestamp(timestamp)
exct_time = value.strftime('%d %B %Y %H:%M:%S')
Get the readable date from timestamp with time also, also you can change the format of the date.
Note that utcfromtimestamp can lead to unexpected results since it returns a naive datetime object. Python treats naive datetime as local time - while UNIX time refers to UTC.
This ambiguity can be avoided by setting the tz argument in fromtimestamp:
from datetime import datetime, timezone
dtobj = datetime.fromtimestamp(1284101485, timezone.utc)
>>> print(repr(dtobj))
datetime.datetime(2010, 9, 10, 6, 51, 25, tzinfo=datetime.timezone.utc)
Now you can format to string, e.g. an ISO8601 compliant format:
>>> print(dtobj.isoformat(timespec='milliseconds').replace('+00:00', 'Z'))
2010-09-10T06:51:25.000Z
Use the following codes, I hope it will solve your problem.
import datetime as dt
print(dt.datetime.fromtimestamp(int("1284101485")).strftime('%Y-%m-%d %H:%M:%S'))
Use datetime.strftime(format):
from datetime import datetime
unixtime = int('1284101485')
# Print with local time
print(datetime.fromtimestamp(unixtime).strftime('%Y-%m-%d %H:%M:%S'))
# Print with UTC time
print(datetime.utcfromtimestamp(unixtime).strftime('%Y-%m-%d %H:%M:%S'))
datetime.fromtimestamp(timestamp): Return the local date corresponding to the POSIX timestamp, such as is returned by time.time().
datetime.utcfromtimestamp(timestamp): Return the UTC datetime corresponding to the POSIX timestamp, with tzinfo None. (The resulting object is naive.)
import datetime
temp = datetime.datetime.fromtimestamp(1386181800).strftime('%Y-%m-%d %H:%M:%S')
print temp
Another way that this can be done using gmtime and format function;
from time import gmtime
print('{}-{}-{} {}:{}:{}'.format(*gmtime(1538654264.703337)))
Output: 2018-10-4 11:57:44
If you are working with a dataframe and do not want the series cannot be converted to class int error. Use the code below.
new_df= pd.to_datetime(df_new['time'], unit='s')
i just successfully used:
>>> type(tstamp)
pandas.tslib.Timestamp
>>> newDt = tstamp.date()
>>> type(newDt)
datetime.date
You can use easy_date to make it easy:
import date_converter
my_date_string = date_converter.timestamp_to_string(1284101485, "%B %d, %Y")
quick and dirty one liner:
'-'.join(str(x) for x in list(tuple(datetime.datetime.now().timetuple())[:6]))
'2013-5-5-1-9-43'