As a beginner, creating timestamps or formatted dates ended up being a little more of a challenge than I would have expected. What are some basic examples for reference?
Ultimately you want to review the datetime documentation and become familiar with the formatting variables, but here are some examples to get you started:
import datetime
print('Timestamp: {:%Y-%m-%d %H:%M:%S}'.format(datetime.datetime.now()))
print('Timestamp: {:%Y-%b-%d %H:%M:%S}'.format(datetime.datetime.now()))
print('Date now: %s' % datetime.datetime.now())
print('Date today: %s' % datetime.date.today())
today = datetime.date.today()
print("Today's date is {:%b, %d %Y}".format(today))
schedule = '{:%b, %d %Y}'.format(today) + ' - 6 PM to 10 PM Pacific'
schedule2 = '{:%B, %d %Y}'.format(today) + ' - 1 PM to 6 PM Central'
print('Maintenance: %s' % schedule)
print('Maintenance: %s' % schedule2)
The output:
Timestamp: 2014-10-18 21:31:12
Timestamp: 2014-Oct-18 21:31:12
Date now: 2014-10-18 21:31:12.318340
Date today: 2014-10-18
Today's date is Oct, 18 2014
Maintenance: Oct, 18 2014 - 6 PM to 10 PM Pacific
Maintenance: October, 18 2014 - 1 PM to 6 PM Central
Reference link: https://docs.python.org/3.4/library/datetime.html#strftime-strptime-behavior
>>> import time
>>> print(time.strftime('%a %H:%M:%S'))
Mon 06:23:14
from datetime import datetime
dt = datetime.now() # for date and time
ts = datetime.timestamp(dt) # for timestamp
print("Date and time is:", dt)
print("Timestamp is:", ts)
You might want to check string to datetime operations for formatting.
from datetime import datetime
datetime_str = '09/19/18 13:55:26'
datetime_object = datetime.strptime(datetime_str, '%m/%d/%y %H:%M:%S')
print(type(datetime_object))
print(datetime_object) # printed in default format
Output:
<class 'datetime.datetime'>
2018-09-19 13:55:26
Related
Through Python i'm trying to convert the future date into another format and subtract with current date but it's throwing error.
Python version = Python 3.6.8
from datetime import datetime
enddate = 'Thu Jun 02 08:00:00 EDT 2022'
todays = datetime.today()
print ('Tpday =',todays)
Modified_date1 = datetime.strptime(enddate, ' %a %b %d %H:%M:%S %Z %Y')
subtract_days= Modified_date1 - todays
print (subtract_days.days)
Output
Today = 2022-02-02 08:06:53.687342
Traceback (most recent call last):
File "1.py", line 106, in trusstore_output
Modified_date1 = datetime.strptime(enddate1, ' %a %b %d %H:%M:%S %Z %Y')
File "/usr/lib64/python3.6/_strptime.py", line 565, in _strptime_datetime
tt, fraction = _strptime(data_string, format)
File "/usr/lib64/python3.6/_strptime.py", line 362, in _strptime
(data_string, format))
ValueError: time data ' Thu Jun 02 08:00:00 EDT 2022' does not match format ' %a %b %d %H:%M:%S %Z %Y'
During handling of the above exception, another exception occurred:
Linux server date
$ date
Wed Feb 2 08:08:36 CST 2022
Point 6 in the Documentation tells that not all Timezone formats are available to be parsed by strptime.
%Z [...]
So someone living in Japan may have JST, UTC, and GMT as valid values, but probably not EST. It will raise ValueError for invalid values.
If possible, you could get the server date with the -u flag and parse the UTC timestamp.
date -u
Mi 2. Feb 14:39:11 UTC 2022
PS:
Also watch out for the leading whitespace in your strings.
If EDT is available on your system, the Value Error could be a result of the a mixup between enddate and enddate1.
' Thu Jun 02 08:00:00 EDT 2022' vs. enddate = 'Thu Jun 02 08:00:00 EDT 2022'
Unfortunately, only a subset of timezones is supported by strptime.
If you can ensure that the input does not contain any other timezones than EDT or EST, you could replace these by the corresponding UTC offsets and use %z instead of %Z:
from datetime import datetime
date_str = "Thu Jun 02 08:00:00 EDT 2022"
date_str = date_str.replace("EDT", "-0400")
date_str = date_str.replace("EST", "-0500")
date_parsed = datetime.strptime(date_str, "%a %b %d %H:%M:%S %z %Y")
# 2022-06-02 08:00:00-04:00
print(date_parsed)
I'm working on a Parser which Parses log files from a game so I can do analysis on auctions made within the game, however the date format that's being written by the logger seems to be causing problems as the format seems to be custom written for the logger, an example datetime stamp looks like: [Wed Nov 23 23:26:10 2016] I try to Parse it with:
func (r *AuctionReader) extractSaleInformation(line string) {
fmt.Println("Extracting information from: ", line)
// Format mask for output
layout := "DD-MM-YYYY hh:mm:ss"
// Replace the square brackets so we're just left with the date-time string
date := strings.TrimSpace(strings.Replace((strings.Split(line, "]")[0]), "[", "", -1))
fmt.Println(time.Parse(date, layout))
}
When I attempt to Parse the above date-time string I get the following error:
0001-01-01 00:00:00 +0000 UTC parsing time "DD-MM-YYYY hh:mm:ss" as "Wed Nov 23 23:26:10 2016": cannot parse "DD-MM-YYYY hh:mm:ss" as "Wed Nov "
How am I able to get the parser to recognise this seemingly custom format, I will be saving this data to Mongo so I don't want to store the auction time as a string as I want to query the timestamps individually.
Golang handle all date formatting in a unique way - it uses the reference time Mon Jan 2 15:04:05 MST 2006 (01/02 03:04:05PM '06 -0700) to show the pattern with which to format/parse a given time/string.
So, to read the format "Wed Nov 23 23:26:10 2016" you would put the reference date into that format: "Mon Jan 2 15:04:05 2006", and then do:
t, _ := time.Parse("Mon Jan 2 15:04:05 2006", "Wed Nov 23 23:26:10 2016")
Then, to output it in the given format, if you wanted the format DD-MM-YYYY hh:mm:ss, you would put the reference time into that format: 02-01-2006 15:04:05, and then do:
t.Format("02-01-2006 15:04:05")
https://play.golang.org/p/VO5413Z7-z
So basically, the main change is
// Format mask for output
layout := "DD-MM-YYYY hh:mm:ss"
should be
// Format mask for output
layout := "02-01-2006 15:04:05"
and
time.Parse(date, layout)
should be
time.Parse(layout, date)
I have a text file (61Gb) containing on each line, a string representing a date, e.g. Thu Dec 16 18:53:32 +0000 2010
Iterating the file on a single core would take too long, therefore I would like to use Pyspark and the Mapreduce technology to quickly find frequencies of lines for a day in a certain year.
What I think is a good start:
import dateutil.parser
text_file = sc.textFile('dates.txt')
date_freqs = text_file.map(lambda line: dateutil.parser.parse(line)) \
.map(lambda date: date + 1) \
.reduceByKey(lambda a, b: a + b)
Unfortunately I can't understand how to filter on a certain year and reduce by key. The key is the day.
Example output:
Thu Dec 16 26543
Thu Dec 17 345
etc.
As alluded to in another answer, dateutil.parser.parse returns a datetime object which has year, month, and day attributes:
>>> dt = dateutil.parser.parse('Thu Dec 16 18:53:32 +0000 2010')
>>> dt.year
2010
>>> dt.month
12
>>> dt.day
16
Starting with this RDD:
>>> rdd = sc.parallelize([
... 'Thu Oct 21 5:12:38 +0000 2010',
... 'Thu Oct 21 4:12:38 +0000 2010',
... 'Wed Sep 22 15:46:40 +0000 2010',
... 'Sun Sep 4 22:28:48 +0000 2011',
... 'Sun Sep 4 21:28:48 +0000 2011'])
Here's how you can get the counts for all year-month-day combinations:
>>> from operator import attrgetter
>>> counts = rdd.map(dateutil.parser.parse).map(
... attrgetter('year', 'month', 'day')).countByValue()
>>> counts
defaultdict(<type 'int'>, {(2010, 9, 22): 1, (2010, 10, 21): 2, (2011, 9, 4): 2})
To get the output you want:
>>> for k, v in counts.iteritems():
... print datetime.datetime(*k).strftime('%a %b %y'), v
...
Wed Sep 10 1
Thu Oct 10 2
Sun Sep 11 2
If you want counts for only a certain year, you can filter the RDD before doing the count:
>>> counts = rdd.map(dateutil.parser.parse).map(
... attrgetter('year', 'month', 'day')).filter(
... lambda (y, m, d): y == 2010).countByValue()
>>> counts
defaultdict(<type 'int'>, {(2010, 9, 22): 1, (2010, 10, 21): 2})
Something along the lines of this might be a good start:
import dateutil.parser
text_file = sc.textFile('dates.txt')
date_freqs = text_file.map(lambda line: dateutil.parser.parse(line))
.keyBy((_.year, _.month, _.day)) // somehow get the year, month, day to key by
.countByKey()
I should add that dateutil is not standard in Python. If you do not have sudo right on your cluster, this could pose a problem. As a solution I would like to propose using datetime:
import datetime
def parse_line(d):
f = "%a %b %d %X %Y"
date_list = d.split()
date = date_list[:4]
date.append(date_list[5])
date = ' '.join(date)
return datetime.datetime.strptime(date, f)
counts = rdd.map(parse_line)\
.map(attrgetter('year', 'month', 'day'))\
.filter(lambda (y, m, d): y == 2015)\
.countByValue()
I am interested in better solutions using: Parquet, Row/Columns etc.
The month format specifier doesn't seem to work.
from datetime import datetime
endDate = datetime.strptime('10 3 2011', '%j %m %Y')
print endDate
2011-01-10 00:00:00
endDate = datetime.strptime('21 5 1987', '%j %m %Y')
print endDate
1987-01-21 00:00:00
Now, according to the manual the manual:
%m = Month as a decimal number [01,12].
So, what am I missing, other than the hair I've pulled out trying to understand why my django __filter queries return nothing (the dates going in aren't valid!)? I've tried 03 and 05 to no avail.
Versions of things, platform, architecture et al:
$ python --version
Python 2.7
$ python3 --version
Python 3.1.2
$ uname -r
2.6.35.11-83.fc14.x86_64 (that's Linux/Fedora 14/64-bit).
You can't mix the %j with others format code like %m because if you look in the table that you linked %j is the Day of the year as a decimal number [001,366] so 10 correspondent to the 10 day of the year so it's 01 of January ...
So you have just to write :
>>> datetime.strptime('10 2011', '%j %Y')
datetime.datetime(2011, 1, 10, 0, 0)
Else if you you wanted to use 10 as the day of the mount you should do :
>>> datetime.strptime('10 3 2011', '%d %m %Y')
datetime.datetime(2011, 3, 10, 0, 0)
Isn't %j the "day of year" parser, which may be forcing strptime to choose January 21, overriding the %m rule?
%j specifies a day of the year. It's impossible for the 10th day of the year, January 10, to occur in March, so your month specification is being ignored. Garbage In, Garbage Out.
I have a tab delimited file where each record has a timestamp field in 12-hour format:
mm/dd/yyyy hh:mm:ss [AM|PM].
I need to quickly convert these fields to 24-hour time:
mm/dd/yyyy HH:mm:ss.
What would be the best way to do this? I'm running on a Windows platform, but I have access to sed, awk, perl, python, and tcl in addition to the usual Windows tools.
Using Perl and hand-crafted regexes instead of facilities like strptime:
#!/bin/perl -w
while (<>)
{
# for date times that don't use leading zeroes, use this regex instead:
# (?:\d{1,2}/\d{1,2}/\d{4} )(\d{1,2})(?::\d\d:\d\d) (AM|PM)
while (m%(?:\d\d/\d\d/\d{4} )(\d\d)(?::\d\d:\d\d) (AM|PM)%)
{
my $hh = $1;
$hh -= 12 if ($2 eq 'AM' && $hh == 12);
$hh += 12 if ($2 eq 'PM' && $hh != 12);
$hh = sprintf "%02d", $hh;
# for date times that don't use leading zeroes, use this regex instead:
# (\d{1,2}/\d{1,2}/\d{4} )(\d{1,2})(:\d\d:\d\d) (?:AM|PM)
s%(\d\d/\d\d/\d{4} )(\d\d)(:\d\d:\d\d) (?:AM|PM)%$1$hh$3%;
}
print;
}
That's very fussy - but also converts possibly multiple timestamps per line.
Note that the transformation for AM/PM to 24-hour is not trivial.
12:01 AM --> 00:01
12:01 PM --> 12:01
01:30 AM --> 01:30
01:30 PM --> 13:30
Now tested:
perl ampm-24hr.pl <<!
12/24/2005 12:01:00 AM
09/22/1999 12:00:00 PM
12/12/2005 01:15:00 PM
01/01/2009 01:56:45 AM
12/30/2009 10:00:00 PM
12/30/2009 10:00:00 AM
!
12/24/2005 00:01:00
09/22/1999 12:00:00
12/12/2005 13:15:00
01/01/2009 01:56:45
12/30/2009 22:00:00
12/30/2009 10:00:00
Added:
In What is a Simple Way to Convert Between an AM/PM Time and 24 hour Time in JavaScript, an alternative algorithm is provided for the conversion:
$hh = ($1 % 12) + (($2 eq 'AM') ? 0 : 12);
Just one test...probably neater.
It is a 1-line thing in python:
time.strftime('%H:%M:%S', time.strptime(x, '%I:%M %p'))
Example:
>>> time.strftime('%H:%M:%S', time.strptime('08:01 AM', '%I:%M %p'))
'08:01:00'
>>> time.strftime('%H:%M:%S', time.strptime('12:01 AM', '%I:%M %p'))
'00:01:00'
Use Pythons datetime module someway like this:
import datetime
infile = open('input.txt')
outfile = open('output.txt', 'w')
for line in infile.readlines():
d = datetime.strptime(line, "input format string")
outfile.write(d.strftime("output format string")
Untested code with no error checking. Also it reads the entire input file in memory before starting.
(I know there is plenty of room for improvements like with statement...I make this a community wiki entry if anyone likes to add something)
To just convert the hour field, in python:
def to12(hour24):
return (hour24 % 12) if (hour24 % 12) > 0 else 12
def IsPM(hour24):
return hour24 > 11
def to24(hour12, isPm):
return (hour12 % 12) + (12 if isPm else 0)
def IsPmString(pm):
return "PM" if pm else "AM"
def TestTo12():
for x in range(24):
print x, to12(x), IsPmString(IsPM(x))
def TestTo24():
for pm in [False, True]:
print 12, IsPmString(pm), to24(12, pm)
for x in range(1, 12):
print x, IsPmString(pm), to24(x, pm)
This might be too simple thinking, but why not import it into excel, select the entire column and change the date format, then re-export as a tab delimited file? (I didn't test this, but it somehow sounds logical to me :)
Here i have converted 24 Hour system to 12 Hour system.
Try to use this method for your problem.
DateFormat fmt = new SimpleDateFormat("yyyyMMddHHssmm");
try {
Date date =fmt.parse("20090310232344");
System.out.println(date.toString());
fmt = new SimpleDateFormat("dd-MMMM-yyyy hh:mm:ss a ");
String dateInString = fmt.format(date);
System.out.println(dateInString);
} catch (Exception e) {
System.out.println(e.getMessage());
}
RESULT:
Tue Mar 10 23:44:23 IST 2009
10-March-2009 11:44:23 PM
In Python: Converting 12hr time to 24hr time
import re
time1=input().strip().split(':')
m=re.search('(..)(..)',time1[2])
sec=m.group(1)
tz=m.group(2)
if(tz='PM'):
time[0]=int(time1[0])+12
if(time1[0]=24):
time1[0]-=12
time[2]=sec
else:
if(int(time1[0])=12):
time1[0]-=12
time[2]=sec
print(time1[0]+':'+time1[1]+':'+time1[2])
Since you have multiple languages, I'll suggest the following algorithm.
1 Check the timestamp for the existence of the "PM" string.
2a If PM does not exist, simply convert the timestamp to the datetime object and proceed.
2b If PM does exist, convert the timestamp to the datetime object, add 12 hours, and proceed.