A Day Has Only 241 Hours Miroslav ediv eumiro 1 / 73 A Day Has - PowerPoint PPT Presentation

A Day Has Only 24±1 Hours Miroslav Š edivý  eumiro 1 / 73

A Day Has Only 24±1 Hours  eumiro  soluteTech 2 / 73

A Day Has Only 24±1 Hours check the time  eumiro  soluteTech 3 / 73

A Day Has Only 24±1 Hours check the time don't check the time too often  eumiro  soluteTech 4 / 73

A Day Has Only 24±1 Hours check the time don't check the time too often check what your government does  eumiro  soluteTech 5 / 73

Miroslav Š edivý [ ˈ m ɪ r ɔ sla ʋ ˈʃɛɟɪ vi ː ]  eumiro  soluteTech 6 / 73

Miroslav Š edivý [ ˈ m ɪ r ɔ sla ʋ ˈʃɛɟɪ vi ː ] born in Bratislava, Czechoslovakia ( TZ=Europe/Bratislava )  eumiro  soluteTech 7 / 73

Miroslav Š edivý [ ˈ m ɪ r ɔ sla ʋ ˈʃɛɟɪ vi ː ] born in Bratislava, Czechoslovakia ( TZ=Europe/Bratislava ) M.Sc. at INSA Lyon, France ( TZ=Europe/Paris )  eumiro  soluteTech 8 / 73

Miroslav Š edivý [ ˈ m ɪ r ɔ sla ʋ ˈʃɛɟɪ vi ː ] born in Bratislava, Czechoslovakia ( TZ=Europe/Bratislava ) M.Sc. at INSA Lyon, France ( TZ=Europe/Paris ) Senior Software Developer at solute GmbH, Karlsruhe, Germany ( TZ=Europe/Berlin )  eumiro  soluteTech 9 / 73

Miroslav Š edivý [ ˈ m ɪ r ɔ sla ʋ ˈʃɛɟɪ vi ː ] born in Bratislava, Czechoslovakia ( TZ=Europe/Bratislava ) M.Sc. at INSA Lyon, France ( TZ=Europe/Paris ) Senior Software Developer at solute GmbH, Karlsruhe, Germany ( TZ=Europe/Berlin ) The whole life in the CE(S)T!  eumiro  soluteTech 10 / 73

 eumiro  soluteTech 11 / 73

Thursday, 11th July 2019 10:33 CEST (Basel, Switzerland)  eumiro  soluteTech 12 / 73

>>> import datetime >>> datetime.datetime.now() datetime.datetime(2019, 7, 11, 10, 33, 0, 0)  eumiro  soluteTech 13 / 73

>>> import datetime >>> datetime.datetime.now() datetime.datetime(2019, 7, 11, 10, 33, 0, 0) datetime.datetime(2019, 7, 11, 8, 33, 0, 0) # server set to UTC  eumiro  soluteTech 14 / 73

>>> import datetime >>> datetime.datetime.now() datetime.datetime(2019, 7, 11, 10, 33, 0, 0) datetime.datetime(2019, 7, 11, 8, 33, 0, 0) # server set to UTC >>> datetime.datetime.utcnow() datetime.datetime(2019, 7, 11, 8, 33, 0, 0)  eumiro  soluteTech 15 / 73

>>> import datetime >>> datetime.datetime.now() datetime.datetime(2019, 7, 11, 10, 33, 0, 0) datetime.datetime(2019, 7, 11, 8, 33, 0, 0) # server set to UTC >>> datetime.datetime.utcnow() datetime.datetime(2019, 7, 11, 8, 33, 0, 0) >>> datetime.datetime.now(datetime.timezone.utc) datetime.datetime(2019, 7, 11, 8, 33, 0, 0, tzinfo=datetime.timezone.utc)  eumiro  soluteTech 16 / 73

>>> import datetime >>> datetime.datetime.now() datetime.datetime(2019, 7, 11, 10, 33, 0, 0) datetime.datetime(2019, 7, 11, 8, 33, 0, 0) # server set to UTC >>> datetime.datetime.utcnow() datetime.datetime(2019, 7, 11, 8, 33, 0, 0) >>> datetime.datetime.now(datetime.timezone.utc) datetime.datetime(2019, 7, 11, 8, 33, 0, 0, tzinfo=datetime.timezone.utc) >>> datetime.datetime.now(datetime.timezone(datetime.timedelta(hours=2))) datetime.datetime(2019, 7, 11, 10, 33, 0, 0, tzinfo=datetime.timezone(datetime.timedelta(0, 7200)))  eumiro  soluteTech 17 / 73

>>> import datetime >>> datetime.datetime.now() datetime.datetime(2019, 7, 11, 10, 33, 0, 0) datetime.datetime(2019, 7, 11, 8, 33, 0, 0) # server set to UTC >>> datetime.datetime.utcnow() datetime.datetime(2019, 7, 11, 8, 33, 0, 0) >>> datetime.datetime.now(datetime.timezone.utc) datetime.datetime(2019, 7, 11, 8, 33, 0, 0, tzinfo=datetime.timezone.utc) >>> datetime.datetime.now(datetime.timezone(datetime.timedelta(hours=2))) datetime.datetime(2019, 7, 11, 10, 33, 0, 0, tzinfo=datetime.timezone(datetime.timedelta(0, 7200))) >>> import pytz >>> datetime.datetime.now(pytz.timezone('Europe/Zurich')) datetime.datetime(2019, 7, 11, 10, 33, 0, 0, tzinfo=<DstTzInfo 'Europe/Zurich' CEST+2:00:00 DST>)  eumiro  soluteTech 18 / 73

>>> datetime.datetime.now(pytz.timezone('Europe/Zurich')) datetime.datetime(2019, 7, 11, 10, 33, 0, 0, tzinfo=<DstTzInfo 'Europe/Zurich' CEST+2:00:00 DST>)  eumiro  soluteTech 19 / 73

>>> datetime.datetime.now(pytz.timezone('Europe/Zurich')) datetime.datetime(2019, 7, 11, 10, 33, 0, 0, tzinfo=<DstTzInfo 'Europe/Zurich' CEST+2:00:00 DST>) >>> datetime.datetime(2019, 7, 11, 10, 33, 0, 0, pytz.timezone('Europe/Zurich')) datetime.datetime(2019, 7, 11, 10, 33, tzinfo=<DstTzInfo 'Europe/Zurich' LMT+0:34:00 STD>)  eumiro  soluteTech 20 / 73

>>> datetime.datetime.now(pytz.timezone('Europe/Zurich')) datetime.datetime(2019, 7, 11, 10, 33, 0, 0, tzinfo=<DstTzInfo 'Europe/Zurich' CEST+2:00:00 DST>) >>> datetime.datetime(2019, 7, 11, 10, 33, 0, 0, pytz.timezone('Europe/Zurich')) datetime.datetime(2019, 7, 11, 10, 33, tzinfo=<DstTzInfo 'Europe/Zurich' LMT+0:34:00 STD>) >>> pytz.timezone('Europe/Zurich').localize(datetime.datetime(2019, 7, 11, 10, 33, 0, 0)) datetime.datetime(2019, 7, 11, 10, 33, tzinfo=<DstTzInfo 'Europe/Zurich' CEST+2:00:00 DST>)  eumiro  soluteTech 21 / 73

>>> datetime.datetime.now(pytz.timezone('Europe/Zurich')) datetime.datetime(2019, 7, 11, 10, 33, 0, 0, tzinfo=<DstTzInfo 'Europe/Zurich' CEST+2:00:00 DST>) >>> datetime.datetime(2019, 7, 11, 10, 33, 0, 0, pytz.timezone('Europe/Zurich')) datetime.datetime(2019, 7, 11, 10, 33, tzinfo=<DstTzInfo 'Europe/Zurich' LMT+0:34:00 STD>) >>> pytz.timezone('Europe/Zurich').localize(datetime.datetime(2019, 7, 11, 10, 33, 0, 0)) datetime.datetime(2019, 7, 11, 10, 33, tzinfo=<DstTzInfo 'Europe/Zurich' CEST+2:00:00 DST>) >>> now + datetime.timedelta(days=184) datetime.datetime(2020, 1, 11, 10, 33, tzinfo=<DstTzInfo 'Europe/Zurich' CEST+2:00:00 DST>)  eumiro  soluteTech 22 / 73

>>> datetime.datetime.now(pytz.timezone('Europe/Zurich')) datetime.datetime(2019, 7, 11, 10, 33, 0, 0, tzinfo=<DstTzInfo 'Europe/Zurich' CEST+2:00:00 DST>) >>> datetime.datetime(2019, 7, 11, 10, 33, 0, 0, pytz.timezone('Europe/Zurich')) datetime.datetime(2019, 7, 11, 10, 33, tzinfo=<DstTzInfo 'Europe/Zurich' LMT+0:34:00 STD>) >>> pytz.timezone('Europe/Zurich').localize(datetime.datetime(2019, 7, 11, 10, 33, 0, 0)) datetime.datetime(2019, 7, 11, 10, 33, tzinfo=<DstTzInfo 'Europe/Zurich' CEST+2:00:00 DST>) >>> now + datetime.timedelta(days=184) datetime.datetime(2020, 1, 11, 10, 33, tzinfo=<DstTzInfo 'Europe/Zurich' CEST+2:00:00 DST>) >>> pytz.timezone('Europe/Zurich').normalize(now + datetime.timedelta(days=184)) datetime.datetime(2020, 1, 11, 9, 33, tzinfo=<DstTzInfo 'Europe/Zurich' CET+1:00:00 STD>)  eumiro  soluteTech 23 / 73

>>> datetime.datetime.now(pytz.timezone('Europe/Zurich')) datetime.datetime(2019, 7, 11, 10, 33, 0, 0, tzinfo=<DstTzInfo 'Europe/Zurich' CEST+2:00:00 DST>) >>> datetime.datetime(2019, 7, 11, 10, 33, 0, 0, pytz.timezone('Europe/Zurich')) datetime.datetime(2019, 7, 11, 10, 33, tzinfo=<DstTzInfo 'Europe/Zurich' LMT+0:34:00 STD>) >>> pytz.timezone('Europe/Zurich').localize(datetime.datetime(2019, 7, 11, 10, 33, 0, 0)) datetime.datetime(2019, 7, 11, 10, 33, tzinfo=<DstTzInfo 'Europe/Zurich' CEST+2:00:00 DST>) >>> now + datetime.timedelta(days=184) datetime.datetime(2020, 1, 11, 10, 33, tzinfo=<DstTzInfo 'Europe/Zurich' CEST+2:00:00 DST>) >>> pytz.timezone('Europe/Zurich').normalize(now + datetime.timedelta(days=184)) datetime.datetime(2020, 1, 11, 9, 33, tzinfo=<DstTzInfo 'Europe/Zurich' CET+1:00:00 STD>) >>> pytz.timezone('Europe/Zurich').localize(now.replace(tzinfo=None) + datetime.timedelta(days=184)) datetime.datetime(2020, 1, 11, 10, 33, tzinfo=<DstTzInfo 'Europe/Zurich' CET+1:00:00 STD>)  eumiro  soluteTech 24 / 73

>>> date = datetime.datetime.utcnow().strftime('%Y-%m-%d') >>> weekday = datetime.datetime.utcnow().strftime('%A') '2019-07-11' 'Thursday'  eumiro  soluteTech 25 / 73

>>> date = datetime.datetime.utcnow().strftime('%Y-%m-%d') >>> weekday = datetime.datetime.utcnow().strftime('%A') '2019-07-11' 'Thursday' >>> now = datetime.datetime.utcnow() >>> date = now.strftime('%Y-%m-%d') >>> weekday = now.strftime('%A')  eumiro  soluteTech 26 / 73

>>> date = datetime.datetime.utcnow().strftime('%Y-%m-%d') >>> weekday = datetime.datetime.utcnow().strftime('%A') '2019-07-11' 'Thursday' >>> now = datetime.datetime.utcnow() >>> date = now.strftime('%Y-%m-%d') >>> weekday = now.strftime('%A') Check the time only once!  eumiro  soluteTech 27 / 73

>>> start = datetime.datetime.utcnow() # datetime.datetime(2019, 7, 11, 8, 33, 0, 0) >>> expensive_operation() >>> end = datetime.datetime.utcnow() # datetime.datetime(2019, 7, 11, 8, 33, 1, 0) >>> elapsed = (end - start).total_seconds() # datetime.timedelta(seconds=1) -> 1.0  eumiro  soluteTech 28 / 73