Python timedelta issue with negative values - python

Hi I need some help to understand why this is happening.
I have a method to track 'time remaining' in an event program:
def get_program_time_budget(self):
return self.estimated_duration-self.get_program_duration()
All fine when the estimated_duration > self.get_program_duration() but when this goes the other way things get funny.
Results are displayed to the user:
Estimated 11 hours Allocated 10 hours 55 minutes Remaining 5 minutes
When the result goes negative it does this:
Estimated 11 hours Allocated 11 hours 5 minutes Remaining -1 day 23 hours 55 minutes
Any ideas how to get the result -5 minutes?
Here is the timedelta formatter (Note this is a Django filter, so receives the timedelta value as a str - but it is stored as a timedelta):
def format_duration(value):
try:
delim = ':'
toks = value.split(',')
hour = minute = ''
d_string = value.count('day') and toks[0] or ''
h, m, s = d_string and toks[-1].strip().split(delim) or value.split(delim)
try:
hour = int(h)
except:
pass
try:
minute = int(m)
except:
pass
h_string = "%s%s%s" % (hour and hour or '', (hour and ' hour' or ''),(hour and hour > 1 and 's' or '') )
m_string = "%s%s%s" % (minute and minute or '', (minute and ' minute' or ''),(minute and minute > 1 and 's' or ''))
return "%s %s %s" % (d_string, h_string, m_string)
except Exception, e:
logging.error("Error in format_duration -> %s. Duration value=%s" % (e, value))
return ''v

If you are using Python 2.7 or higher you can use timedelta.total_seconds() to get a float representation of the timedelta as a positive or negative number of seconds.
>>> datetime.timedelta(-1, 86100).total_seconds()
-300.0
You should be able to use this to calculate a number of minutes fairly easily.
If you are not using Python 2.7 you can use the following equivalent formula from the docs:
(td.microseconds + (td.seconds + td.days * 24 * 3600) * 10**6) / 10.0**6
Edit: It looks like you are probably using the default string representation for timedelta to display the result, so my original answer may not be as useful. I would suggest something like this for displaying the result:
def get_program_time_budget(self):
td = self.estimated_duration-self.get_program_duration()
if td.days < 0:
return '-' + str(datetime.timedelta() - td)
return str(td)
This would now return a string instead of a timedelta, and for negative timedeltas it would prepend a '-' to a positive timedelta.

Why?
Possibly as a unintended side effect of the way // and % are defined.
Possibly because it makes it easier to implement the datetime class. Five minutes before the epoch is 23:55, not 0:-5.
It doesn't really matter. Just know that it's how days, seconds, and microseconds get normalized. And that it can easily be worked around.
def format_timedelta(td):
if td < timedelta(0):
return '-' + format_timedelta(-td)
else:
# Change this to format positive timedeltas the way you want
return str(td)
>>> format_timedelta(timedelta(minutes=-5))
'-0:05:00'

Also if you are facing problems with a timedelta object containing negative values even though the values should be positive, you can use pythons builtin abs(td_object)
>>> current_time = datetime.datetime.now()
>>> fifteen_seconds = datetime.timedelta(seconds=15)
>>> time_delta_after_calculations = current_time - (current_time + fifteen_seconds) # It should give a timedelta with 15 seconds but it does not
>>> time_delta_after_calculations
datetime.timedelta(days=-1, seconds=86385)
>>> # The above is kind of True but not what expected (A day contains 86400 seconds)
>>> abs(time_delta_after_calculations) # Gives expected output
datetime.timedelta(seconds=15)

Related

After subtracting one datetime from another to get a timedelta, how can I standardise the format to always have the number of days at the front? [duplicate]

I'm having trouble formatting a datetime.timedelta object.
Here's what I'm trying to do:
I have a list of objects and one of the members of the class of the object is a timedelta object that shows the duration of an event. I would like to display that duration in the format of hours:minutes.
I have tried a variety of methods for doing this and I'm having difficulty. My current approach is to add methods to the class for my objects that return hours and minutes. I can get the hours by dividing the timedelta.seconds by 3600 and rounding it. I'm having trouble with getting the remainder seconds and converting that to minutes.
By the way, I'm using Google AppEngine with Django Templates for presentation.
You can just convert the timedelta to a string with str(). Here's an example:
import datetime
start = datetime.datetime(2009,2,10,14,00)
end = datetime.datetime(2009,2,10,16,00)
delta = end-start
print(str(delta))
# prints 2:00:00
As you know, you can get the total_seconds from a timedelta object by accessing the .seconds attribute.
Python provides the builtin function divmod() which allows for:
s = 13420
hours, remainder = divmod(s, 3600)
minutes, seconds = divmod(remainder, 60)
print('{:02}:{:02}:{:02}'.format(int(hours), int(minutes), int(seconds)))
# result: 03:43:40
or you can convert to hours and remainder by using a combination of modulo and subtraction:
# arbitrary number of seconds
s = 13420
# hours
hours = s // 3600
# remaining seconds
s = s - (hours * 3600)
# minutes
minutes = s // 60
# remaining seconds
seconds = s - (minutes * 60)
# total time
print('{:02}:{:02}:{:02}'.format(int(hours), int(minutes), int(seconds)))
# result: 03:43:40
>>> str(datetime.timedelta(hours=10.56))
10:33:36
>>> td = datetime.timedelta(hours=10.505) # any timedelta object
>>> ':'.join(str(td).split(':')[:2])
10:30
Passing the timedelta object to the str() function calls the same formatting code used if we simply type print td. Since you don't want the seconds, we can split the string by colons (3 parts) and put it back together with only the first 2 parts.
def td_format(td_object):
seconds = int(td_object.total_seconds())
periods = [
('year', 60*60*24*365),
('month', 60*60*24*30),
('day', 60*60*24),
('hour', 60*60),
('minute', 60),
('second', 1)
]
strings=[]
for period_name, period_seconds in periods:
if seconds > period_seconds:
period_value , seconds = divmod(seconds, period_seconds)
has_s = 's' if period_value > 1 else ''
strings.append("%s %s%s" % (period_value, period_name, has_s))
return ", ".join(strings)
I personally use the humanize library for this:
>>> import datetime
>>> humanize.naturalday(datetime.datetime.now())
'today'
>>> humanize.naturalday(datetime.datetime.now() - datetime.timedelta(days=1))
'yesterday'
>>> humanize.naturalday(datetime.date(2007, 6, 5))
'Jun 05'
>>> humanize.naturaldate(datetime.date(2007, 6, 5))
'Jun 05 2007'
>>> humanize.naturaltime(datetime.datetime.now() - datetime.timedelta(seconds=1))
'a second ago'
>>> humanize.naturaltime(datetime.datetime.now() - datetime.timedelta(seconds=3600))
'an hour ago'
Of course, it doesn't give you exactly the answer you were looking for (which is, indeed, str(timeA - timeB), but I have found that once you go beyond a few hours, the display becomes quickly unreadable. humanize has support for much larger values that are human-readable, and is also well localized.
It's inspired by Django's contrib.humanize module, apparently, so since you are using Django, you should probably use that.
He already has a timedelta object so why not use its built-in method total_seconds() to convert it to seconds, then use divmod() to get hours and minutes?
hours, remainder = divmod(myTimeDelta.total_seconds(), 3600)
minutes, seconds = divmod(remainder, 60)
# Formatted only for hours and minutes as requested
print '%s:%s' % (hours, minutes)
This works regardless if the time delta has even days or years.
Here is a general purpose function for converting either a timedelta object or a regular number (in the form of seconds or minutes, etc.) to a nicely formatted string. I took mpounsett's fantastic answer on a duplicate question, made it a bit more flexible, improved readibility, and added documentation.
You will find that it is the most flexible answer here so far since it allows you to:
Customize the string format on the fly instead of it being hard-coded.
Leave out certain time intervals without a problem (see examples below).
Function:
from string import Formatter
from datetime import timedelta
def strfdelta(tdelta, fmt='{D:02}d {H:02}h {M:02}m {S:02}s', inputtype='timedelta'):
"""Convert a datetime.timedelta object or a regular number to a custom-
formatted string, just like the stftime() method does for datetime.datetime
objects.
The fmt argument allows custom formatting to be specified. Fields can
include seconds, minutes, hours, days, and weeks. Each field is optional.
Some examples:
'{D:02}d {H:02}h {M:02}m {S:02}s' --> '05d 08h 04m 02s' (default)
'{W}w {D}d {H}:{M:02}:{S:02}' --> '4w 5d 8:04:02'
'{D:2}d {H:2}:{M:02}:{S:02}' --> ' 5d 8:04:02'
'{H}h {S}s' --> '72h 800s'
The inputtype argument allows tdelta to be a regular number instead of the
default, which is a datetime.timedelta object. Valid inputtype strings:
's', 'seconds',
'm', 'minutes',
'h', 'hours',
'd', 'days',
'w', 'weeks'
"""
# Convert tdelta to integer seconds.
if inputtype == 'timedelta':
remainder = int(tdelta.total_seconds())
elif inputtype in ['s', 'seconds']:
remainder = int(tdelta)
elif inputtype in ['m', 'minutes']:
remainder = int(tdelta)*60
elif inputtype in ['h', 'hours']:
remainder = int(tdelta)*3600
elif inputtype in ['d', 'days']:
remainder = int(tdelta)*86400
elif inputtype in ['w', 'weeks']:
remainder = int(tdelta)*604800
f = Formatter()
desired_fields = [field_tuple[1] for field_tuple in f.parse(fmt)]
possible_fields = ('W', 'D', 'H', 'M', 'S')
constants = {'W': 604800, 'D': 86400, 'H': 3600, 'M': 60, 'S': 1}
values = {}
for field in possible_fields:
if field in desired_fields and field in constants:
values[field], remainder = divmod(remainder, constants[field])
return f.format(fmt, **values)
Demo:
>>> td = timedelta(days=2, hours=3, minutes=5, seconds=8, microseconds=340)
>>> print strfdelta(td)
02d 03h 05m 08s
>>> print strfdelta(td, '{D}d {H}:{M:02}:{S:02}')
2d 3:05:08
>>> print strfdelta(td, '{D:2}d {H:2}:{M:02}:{S:02}')
2d 3:05:08
>>> print strfdelta(td, '{H}h {S}s')
51h 308s
>>> print strfdelta(12304, inputtype='s')
00d 03h 25m 04s
>>> print strfdelta(620, '{H}:{M:02}', 'm')
10:20
>>> print strfdelta(49, '{D}d {H}h', 'h')
2d 1h
I know that this is an old answered question, but I use datetime.utcfromtimestamp() for this. It takes the number of seconds and returns a datetime that can be formatted like any other datetime.
duration = datetime.utcfromtimestamp(end - begin)
print duration.strftime('%H:%M')
As long as you stay in the legal ranges for the time parts this should work, i.e. it doesn't return 1234:35 as hours are <= 23.
maybe:
>>> import datetime
>>> dt0 = datetime.datetime(1,1,1)
>>> td = datetime.timedelta(minutes=34, hours=12, seconds=56)
>>> (dt0+td).strftime('%X')
'12:34:56'
>>> (dt0+td).strftime('%M:%S')
'34:56'
>>> (dt0+td).strftime('%H:%M')
'12:34'
>>>
I would seriously consider the Occam's Razor approach here:
td = str(timedelta).split('.')[0]
This returns a string without the microseconds
If you want to regenerate the datetime.timedelta object, just do this:
h,m,s = re.split(':', td)
new_delta = datetime.timedelta(hours=int(h),minutes=int(m),seconds=int(s))
2 years in, I love this language!
I used the humanfriendly python library to do this, it works very well.
import humanfriendly
from datetime import timedelta
delta = timedelta(seconds = 321)
humanfriendly.format_timespan(delta)
'5 minutes and 21 seconds'
Available at https://pypi.org/project/humanfriendly/
Questioner wants a nicer format than the typical:
>>> import datetime
>>> datetime.timedelta(seconds=41000)
datetime.timedelta(0, 41000)
>>> str(datetime.timedelta(seconds=41000))
'11:23:20'
>>> str(datetime.timedelta(seconds=4102.33))
'1:08:22.330000'
>>> str(datetime.timedelta(seconds=413302.33))
'4 days, 18:48:22.330000'
So, really there's two formats, one where days are 0 and it's left out, and another where there's text "n days, h:m:s". But, the seconds may have fractions, and there's no leading zeroes in the printouts, so columns are messy.
Here's my routine, if you like it:
def printNiceTimeDelta(stime, etime):
delay = datetime.timedelta(seconds=(etime - stime))
if (delay.days > 0):
out = str(delay).replace(" days, ", ":")
else:
out = "0:" + str(delay)
outAr = out.split(':')
outAr = ["%02d" % (int(float(x))) for x in outAr]
out = ":".join(outAr)
return out
this returns output as dd:hh:mm:ss format:
00:00:00:15
00:00:00:19
02:01:31:40
02:01:32:22
I did think about adding years to this, but this is left as an exercise for the reader, since the output is safe at over 1 year:
>>> str(datetime.timedelta(seconds=99999999))
'1157 days, 9:46:39'
My datetime.timedelta objects went greater than a day. So here is a further problem. All the discussion above assumes less than a day. A timedelta is actually a tuple of days, seconds and microseconds. The above discussion should use td.seconds as joe did, but if you have days it is NOT included in the seconds value.
I am getting a span of time between 2 datetimes and printing days and hours.
span = currentdt - previousdt
print '%d,%d\n' % (span.days,span.seconds/3600)
I have a function:
def period(delta, pattern):
d = {'d': delta.days}
d['h'], rem = divmod(delta.seconds, 3600)
d['m'], d['s'] = divmod(rem, 60)
return pattern.format(**d)
Examples:
>>> td = timedelta(seconds=123456789)
>>> period(td, "{d} days {h}:{m}:{s}")
'1428 days 21:33:9'
>>> period(td, "{h} hours, {m} minutes and {s} seconds, {d} days")
'21 hours, 33 minutes and 9 seconds, 1428 days'
Following Joe's example value above, I'd use the modulus arithmetic operator, thusly:
td = datetime.timedelta(hours=10.56)
td_str = "%d:%d" % (td.seconds/3600, td.seconds%3600/60)
Note that integer division in Python rounds down by default; if you want to be more explicit, use math.floor() or math.ceil() as appropriate.
One liner. Since timedeltas do not offer datetime's strftime, bring the timedelta back to a datetime, and use stftime.
This can not only achieve the OP's requested format Hours:Minutes, now you can leverage the full formatting power of datetime's strftime, should your requirements change to another representation.
import datetime
td = datetime.timedelta(hours=2, minutes=10, seconds=5)
print(td)
print(datetime.datetime.strftime(datetime.datetime.strptime(str(td), "%H:%M:%S"), "%H:%M"))
Output:
2:10:05
02:10
This also solves the annoyance that timedeltas are formatted into strings as H:MM:SS rather than HH:MM:SS, which lead me to this problem, and the solution I've shared.
import datetime
hours = datetime.timedelta(hours=16, minutes=30)
print((datetime.datetime(1,1,1) + hours).strftime('%H:%M'))
def seconds_to_time_left_string(total_seconds):
s = int(total_seconds)
years = s // 31104000
if years > 1:
return '%d years' % years
s = s - (years * 31104000)
months = s // 2592000
if years == 1:
r = 'one year'
if months > 0:
r += ' and %d months' % months
return r
if months > 1:
return '%d months' % months
s = s - (months * 2592000)
days = s // 86400
if months == 1:
r = 'one month'
if days > 0:
r += ' and %d days' % days
return r
if days > 1:
return '%d days' % days
s = s - (days * 86400)
hours = s // 3600
if days == 1:
r = 'one day'
if hours > 0:
r += ' and %d hours' % hours
return r
s = s - (hours * 3600)
minutes = s // 60
seconds = s - (minutes * 60)
if hours >= 6:
return '%d hours' % hours
if hours >= 1:
r = '%d hours' % hours
if hours == 1:
r = 'one hour'
if minutes > 0:
r += ' and %d minutes' % minutes
return r
if minutes == 1:
r = 'one minute'
if seconds > 0:
r += ' and %d seconds' % seconds
return r
if minutes == 0:
return '%d seconds' % seconds
if seconds == 0:
return '%d minutes' % minutes
return '%d minutes and %d seconds' % (minutes, seconds)
for i in range(10):
print pow(8, i), seconds_to_time_left_string(pow(8, i))
Output:
1 1 seconds
8 8 seconds
64 one minute and 4 seconds
512 8 minutes and 32 seconds
4096 one hour and 8 minutes
32768 9 hours
262144 3 days
2097152 24 days
16777216 6 months
134217728 4 years
I had a similar problem with the output of overtime calculation at work. The value should always show up in HH:MM, even when it is greater than one day and the value can get negative. I combined some of the shown solutions and maybe someone else find this solution useful. I realized that if the timedelta value is negative most of the shown solutions with the divmod method doesn't work out of the box:
def td2HHMMstr(td):
'''Convert timedelta objects to a HH:MM string with (+/-) sign'''
if td < datetime.timedelta(seconds=0):
sign='-'
td = -td
else:
sign = ''
tdhours, rem = divmod(td.total_seconds(), 3600)
tdminutes, rem = divmod(rem, 60)
tdstr = '{}{:}:{:02d}'.format(sign, int(tdhours), int(tdminutes))
return tdstr
timedelta to HH:MM string:
td2HHMMstr(datetime.timedelta(hours=1, minutes=45))
'1:54'
td2HHMMstr(datetime.timedelta(days=2, hours=3, minutes=2))
'51:02'
td2HHMMstr(datetime.timedelta(hours=-3, minutes=-2))
'-3:02'
td2HHMMstr(datetime.timedelta(days=-35, hours=-3, minutes=-2))
'-843:02'
from django.utils.translation import ngettext
def localize_timedelta(delta):
ret = []
num_years = int(delta.days / 365)
if num_years > 0:
delta -= timedelta(days=num_years * 365)
ret.append(ngettext('%d year', '%d years', num_years) % num_years)
if delta.days > 0:
ret.append(ngettext('%d day', '%d days', delta.days) % delta.days)
num_hours = int(delta.seconds / 3600)
if num_hours > 0:
delta -= timedelta(hours=num_hours)
ret.append(ngettext('%d hour', '%d hours', num_hours) % num_hours)
num_minutes = int(delta.seconds / 60)
if num_minutes > 0:
ret.append(ngettext('%d minute', '%d minutes', num_minutes) % num_minutes)
return ' '.join(ret)
This will produce:
>>> from datetime import timedelta
>>> localize_timedelta(timedelta(days=3660, minutes=500))
'10 years 10 days 8 hours 20 minutes'
A straight forward template filter for this problem. The built-in function int() never rounds up. F-Strings (i.e. f'') require python 3.6.
#app_template_filter()
def diffTime(end, start):
diff = (end - start).total_seconds()
d = int(diff / 86400)
h = int((diff - (d * 86400)) / 3600)
m = int((diff - (d * 86400 + h * 3600)) / 60)
s = int((diff - (d * 86400 + h * 3600 + m *60)))
if d > 0:
fdiff = f'{d}d {h}h {m}m {s}s'
elif h > 0:
fdiff = f'{h}h {m}m {s}s'
elif m > 0:
fdiff = f'{m}m {s}s'
else:
fdiff = f'{s}s'
return fdiff
If you happen to have IPython in your packages (you should), it has (up to now, anyway) a very nice formatter for durations (in float seconds). That is used in various places, for example by the %%time cell magic. I like the format it produces for short durations:
>>> from IPython.core.magics.execution import _format_time
>>>
>>> for v in range(-9, 10, 2):
... dt = 1.25 * 10**v
... print(_format_time(dt))
1.25 ns
125 ns
12.5 µs
1.25 ms
125 ms
12.5 s
20min 50s
1d 10h 43min 20s
144d 16h 13min 20s
14467d 14h 13min 20s
I continued from MarredCheese's answer and added year, month, millicesond and microsecond
all numbers are formatted to integer except for second, thus the fraction of a second can be customized.
#kfmfe04 asked for fraction of a second so I posted this solution
In the main there are some examples.
from string import Formatter
from datetime import timedelta
def strfdelta(tdelta, fmt='{D:02}d {H:02}h {M:02}m {S:02.0f}s', inputtype='timedelta'):
"""Convert a datetime.timedelta object or a regular number to a custom-
formatted string, just like the stftime() method does for datetime.datetime
objects.
The fmt argument allows custom formatting to be specified. Fields can
include seconds, minutes, hours, days, and weeks. Each field is optional.
Some examples:
'{D:02}d {H:02}h {M:02}m {S:02.0f}s' --> '05d 08h 04m 02s' (default)
'{W}w {D}d {H}:{M:02}:{S:02.0f}' --> '4w 5d 8:04:02'
'{D:2}d {H:2}:{M:02}:{S:02.0f}' --> ' 5d 8:04:02'
'{H}h {S:.0f}s' --> '72h 800s'
The inputtype argument allows tdelta to be a regular number instead of the
default, which is a datetime.timedelta object. Valid inputtype strings:
's', 'seconds',
'm', 'minutes',
'h', 'hours',
'd', 'days',
'w', 'weeks'
"""
# Convert tdelta to integer seconds.
if inputtype == 'timedelta':
remainder = tdelta.total_seconds()
elif inputtype in ['s', 'seconds']:
remainder = float(tdelta)
elif inputtype in ['m', 'minutes']:
remainder = float(tdelta)*60
elif inputtype in ['h', 'hours']:
remainder = float(tdelta)*3600
elif inputtype in ['d', 'days']:
remainder = float(tdelta)*86400
elif inputtype in ['w', 'weeks']:
remainder = float(tdelta)*604800
f = Formatter()
desired_fields = [field_tuple[1] for field_tuple in f.parse(fmt)]
possible_fields = ('Y','m','W', 'D', 'H', 'M', 'S', 'mS', 'µS')
constants = {'Y':86400*365.24,'m': 86400*30.44 ,'W': 604800, 'D': 86400, 'H': 3600, 'M': 60, 'S': 1, 'mS': 1/pow(10,3) , 'µS':1/pow(10,6)}
values = {}
for field in possible_fields:
if field in desired_fields and field in constants:
Quotient, remainder = divmod(remainder, constants[field])
values[field] = int(Quotient) if field != 'S' else Quotient + remainder
return f.format(fmt, **values)
if __name__ == "__main__":
td = timedelta(days=717, hours=3, minutes=5, seconds=8, microseconds=3549)
print(strfdelta(td,'{Y} years {m} months {W} weeks {D} days {H:02}:{M:02}:{S:02}'))
print(strfdelta(td,'{m} months {W} weeks {D} days {H:02}:{M:02}:{S:02.4f}'))
td = timedelta( seconds=8, microseconds=8549)
print(strfdelta(td,'{S} seconds {mS} milliseconds {µS} microseconds'))
print(strfdelta(td,'{S:.0f} seconds {mS} milliseconds {µS} microseconds'))
print(strfdelta(pow(10,7),inputtype='s'))
Output:
1 years 11 months 2 weeks 3 days 01:09:56.00354900211096
23 months 2 weeks 3 days 00:12:20.0035
8.008549 seconds 8 milliseconds 549 microseconds
8 seconds 8 milliseconds 549 microseconds
115d 17h 46m 40s
Here's a function to stringify timedelta.total_seconds(). It works in python 2 and 3.
def strf_interval(seconds):
days, remainder = divmod(seconds, 86400)
hours, remainder = divmod(remainder, 3600)
minutes, seconds = divmod(remainder, 60)
return '{} {} {} {}'.format(
"" if int(days) == 0 else str(int(days)) + ' days',
"" if int(hours) == 0 else str(int(hours)) + ' hours',
"" if int(minutes) == 0 else str(int(minutes)) + ' mins',
"" if int(seconds) == 0 else str(int(seconds)) + ' secs'
)
Example output:
>>> print(strf_interval(1))
1 secs
>>> print(strf_interval(100))
1 mins 40 secs
>>> print(strf_interval(1000))
16 mins 40 secs
>>> print(strf_interval(10000))
2 hours 46 mins 40 secs
>>> print(strf_interval(100000))
1 days 3 hours 46 mins 40 secs
timedelta to string, use for print running time info.
def strfdelta_round(tdelta, round_period='second'):
"""timedelta to string, use for measure running time
attend period from days downto smaller period, round to minimum period
omit zero value period
"""
period_names = ('day', 'hour', 'minute', 'second', 'millisecond')
if round_period not in period_names:
raise Exception(f'round_period "{round_period}" invalid, should be one of {",".join(period_names)}')
period_seconds = (86400, 3600, 60, 1, 1/pow(10,3))
period_desc = ('days', 'hours', 'mins', 'secs', 'msecs')
round_i = period_names.index(round_period)
s = ''
remainder = tdelta.total_seconds()
for i in range(len(period_names)):
q, remainder = divmod(remainder, period_seconds[i])
if int(q)>0:
if not len(s)==0:
s += ' '
s += f'{q:.0f} {period_desc[i]}'
if i==round_i:
break
if i==round_i+1:
s += f'{remainder} {period_desc[round_i]}'
break
return s
e.g. auto omit zero leading period:
>>> td = timedelta(days=0, hours=2, minutes=5, seconds=8, microseconds=3549)
>>> strfdelta_round(td, 'second')
'2 hours 5 mins 8 secs'
or omit middle zero period:
>>> td = timedelta(days=2, hours=0, minutes=5, seconds=8, microseconds=3549)
>>> strfdelta_round(td, 'millisecond')
'2 days 5 mins 8 secs 3 msecs'
or round to minutes, omit below minutes:
>>> td = timedelta(days=1, hours=2, minutes=5, seconds=8, microseconds=3549)
>>> strfdelta_round(td, 'minute')
'1 days 2 hours 5 mins'
Please check this function - it converts timedelta object into string 'HH:MM:SS'
def format_timedelta(td):
hours, remainder = divmod(td.total_seconds(), 3600)
minutes, seconds = divmod(remainder, 60)
hours, minutes, seconds = int(hours), int(minutes), int(seconds)
if hours < 10:
hours = '0%s' % int(hours)
if minutes < 10:
minutes = '0%s' % minutes
if seconds < 10:
seconds = '0%s' % seconds
return '%s:%s:%s' % (hours, minutes, seconds)
If you already have a timedelta obj then just convert that obj into string. Remove the last 3 characters of the string and print. This will truncate the seconds part and print the rest of it in the format Hours:Minutes.
t = str(timedeltaobj)
print t[:-3]
I wanted to do this so wrote a simple function. It works great for me and is quite versatile (supports years to microseconds, and any granularity level, e.g. you can pick between '2 days, 4 hours, 48 minutes' and '2 days, 4 hours' and '2 days, 4.8 hours', etc.
def pretty_print_timedelta(t, max_components=None, max_decimal_places=2):
'''
Print a pretty string for a timedelta.
For example datetime.timedelta(days=2, seconds=17280) will be printed as '2 days, 4 hours, 48 minutes'. Setting max_components to e.g. 1 will change this to '2.2 days', where the
number of decimal points can also be set.
'''
time_scales = [timedelta(days=365), timedelta(days=1), timedelta(hours=1), timedelta(minutes=1), timedelta(seconds=1), timedelta(microseconds=1000), timedelta(microseconds=1)]
time_scale_names_dict = {timedelta(days=365): 'year',
timedelta(days=1): 'day',
timedelta(hours=1): 'hour',
timedelta(minutes=1): 'minute',
timedelta(seconds=1): 'second',
timedelta(microseconds=1000): 'millisecond',
timedelta(microseconds=1): 'microsecond'}
count = 0
txt = ''
first = True
for scale in time_scales:
if t >= scale:
count += 1
if count == max_components:
n = t / scale
else:
n = int(t / scale)
t -= n*scale
n_txt = str(round(n, max_decimal_places))
if n_txt[-2:]=='.0': n_txt = n_txt[:-2]
txt += '{}{} {}{}'.format('' if first else ', ', n_txt, time_scale_names_dict[scale], 's' if n>1 else '', )
if first:
first = False
if len(txt) == 0:
txt = 'none'
return txt
I had the same problem and I am using pandas Timedeltas, didn't want to bring in additional dependencies (another answer mentions humanfriendly) so I wrote this small function to print out only the relevant information:
def format_timedelta(td: pd.Timedelta) -> str:
if pd.isnull(td):
return str(td)
else:
c = td.components._asdict()
return ", ".join(f"{n} {unit}" for unit, n in c.items() if n)
For example, pd.Timedelta(hours=3, seconds=12) would print as 3 hours, 12 seconds.
I suggest the following method so that we can utilize the standard formatting function, pandas.Timestamp.strftime!
from pandas import Timestamp, Timedelta
(Timedelta("2 hours 30 min") + Timestamp("00:00:00")).strftime("%H:%M")

Problem adding difference of two timestamps in txt file in python [duplicate]

I'm having trouble formatting a datetime.timedelta object.
Here's what I'm trying to do:
I have a list of objects and one of the members of the class of the object is a timedelta object that shows the duration of an event. I would like to display that duration in the format of hours:minutes.
I have tried a variety of methods for doing this and I'm having difficulty. My current approach is to add methods to the class for my objects that return hours and minutes. I can get the hours by dividing the timedelta.seconds by 3600 and rounding it. I'm having trouble with getting the remainder seconds and converting that to minutes.
By the way, I'm using Google AppEngine with Django Templates for presentation.
You can just convert the timedelta to a string with str(). Here's an example:
import datetime
start = datetime.datetime(2009,2,10,14,00)
end = datetime.datetime(2009,2,10,16,00)
delta = end-start
print(str(delta))
# prints 2:00:00
As you know, you can get the total_seconds from a timedelta object by accessing the .seconds attribute.
Python provides the builtin function divmod() which allows for:
s = 13420
hours, remainder = divmod(s, 3600)
minutes, seconds = divmod(remainder, 60)
print('{:02}:{:02}:{:02}'.format(int(hours), int(minutes), int(seconds)))
# result: 03:43:40
or you can convert to hours and remainder by using a combination of modulo and subtraction:
# arbitrary number of seconds
s = 13420
# hours
hours = s // 3600
# remaining seconds
s = s - (hours * 3600)
# minutes
minutes = s // 60
# remaining seconds
seconds = s - (minutes * 60)
# total time
print('{:02}:{:02}:{:02}'.format(int(hours), int(minutes), int(seconds)))
# result: 03:43:40
>>> str(datetime.timedelta(hours=10.56))
10:33:36
>>> td = datetime.timedelta(hours=10.505) # any timedelta object
>>> ':'.join(str(td).split(':')[:2])
10:30
Passing the timedelta object to the str() function calls the same formatting code used if we simply type print td. Since you don't want the seconds, we can split the string by colons (3 parts) and put it back together with only the first 2 parts.
def td_format(td_object):
seconds = int(td_object.total_seconds())
periods = [
('year', 60*60*24*365),
('month', 60*60*24*30),
('day', 60*60*24),
('hour', 60*60),
('minute', 60),
('second', 1)
]
strings=[]
for period_name, period_seconds in periods:
if seconds > period_seconds:
period_value , seconds = divmod(seconds, period_seconds)
has_s = 's' if period_value > 1 else ''
strings.append("%s %s%s" % (period_value, period_name, has_s))
return ", ".join(strings)
I personally use the humanize library for this:
>>> import datetime
>>> humanize.naturalday(datetime.datetime.now())
'today'
>>> humanize.naturalday(datetime.datetime.now() - datetime.timedelta(days=1))
'yesterday'
>>> humanize.naturalday(datetime.date(2007, 6, 5))
'Jun 05'
>>> humanize.naturaldate(datetime.date(2007, 6, 5))
'Jun 05 2007'
>>> humanize.naturaltime(datetime.datetime.now() - datetime.timedelta(seconds=1))
'a second ago'
>>> humanize.naturaltime(datetime.datetime.now() - datetime.timedelta(seconds=3600))
'an hour ago'
Of course, it doesn't give you exactly the answer you were looking for (which is, indeed, str(timeA - timeB), but I have found that once you go beyond a few hours, the display becomes quickly unreadable. humanize has support for much larger values that are human-readable, and is also well localized.
It's inspired by Django's contrib.humanize module, apparently, so since you are using Django, you should probably use that.
He already has a timedelta object so why not use its built-in method total_seconds() to convert it to seconds, then use divmod() to get hours and minutes?
hours, remainder = divmod(myTimeDelta.total_seconds(), 3600)
minutes, seconds = divmod(remainder, 60)
# Formatted only for hours and minutes as requested
print '%s:%s' % (hours, minutes)
This works regardless if the time delta has even days or years.
Here is a general purpose function for converting either a timedelta object or a regular number (in the form of seconds or minutes, etc.) to a nicely formatted string. I took mpounsett's fantastic answer on a duplicate question, made it a bit more flexible, improved readibility, and added documentation.
You will find that it is the most flexible answer here so far since it allows you to:
Customize the string format on the fly instead of it being hard-coded.
Leave out certain time intervals without a problem (see examples below).
Function:
from string import Formatter
from datetime import timedelta
def strfdelta(tdelta, fmt='{D:02}d {H:02}h {M:02}m {S:02}s', inputtype='timedelta'):
"""Convert a datetime.timedelta object or a regular number to a custom-
formatted string, just like the stftime() method does for datetime.datetime
objects.
The fmt argument allows custom formatting to be specified. Fields can
include seconds, minutes, hours, days, and weeks. Each field is optional.
Some examples:
'{D:02}d {H:02}h {M:02}m {S:02}s' --> '05d 08h 04m 02s' (default)
'{W}w {D}d {H}:{M:02}:{S:02}' --> '4w 5d 8:04:02'
'{D:2}d {H:2}:{M:02}:{S:02}' --> ' 5d 8:04:02'
'{H}h {S}s' --> '72h 800s'
The inputtype argument allows tdelta to be a regular number instead of the
default, which is a datetime.timedelta object. Valid inputtype strings:
's', 'seconds',
'm', 'minutes',
'h', 'hours',
'd', 'days',
'w', 'weeks'
"""
# Convert tdelta to integer seconds.
if inputtype == 'timedelta':
remainder = int(tdelta.total_seconds())
elif inputtype in ['s', 'seconds']:
remainder = int(tdelta)
elif inputtype in ['m', 'minutes']:
remainder = int(tdelta)*60
elif inputtype in ['h', 'hours']:
remainder = int(tdelta)*3600
elif inputtype in ['d', 'days']:
remainder = int(tdelta)*86400
elif inputtype in ['w', 'weeks']:
remainder = int(tdelta)*604800
f = Formatter()
desired_fields = [field_tuple[1] for field_tuple in f.parse(fmt)]
possible_fields = ('W', 'D', 'H', 'M', 'S')
constants = {'W': 604800, 'D': 86400, 'H': 3600, 'M': 60, 'S': 1}
values = {}
for field in possible_fields:
if field in desired_fields and field in constants:
values[field], remainder = divmod(remainder, constants[field])
return f.format(fmt, **values)
Demo:
>>> td = timedelta(days=2, hours=3, minutes=5, seconds=8, microseconds=340)
>>> print strfdelta(td)
02d 03h 05m 08s
>>> print strfdelta(td, '{D}d {H}:{M:02}:{S:02}')
2d 3:05:08
>>> print strfdelta(td, '{D:2}d {H:2}:{M:02}:{S:02}')
2d 3:05:08
>>> print strfdelta(td, '{H}h {S}s')
51h 308s
>>> print strfdelta(12304, inputtype='s')
00d 03h 25m 04s
>>> print strfdelta(620, '{H}:{M:02}', 'm')
10:20
>>> print strfdelta(49, '{D}d {H}h', 'h')
2d 1h
I know that this is an old answered question, but I use datetime.utcfromtimestamp() for this. It takes the number of seconds and returns a datetime that can be formatted like any other datetime.
duration = datetime.utcfromtimestamp(end - begin)
print duration.strftime('%H:%M')
As long as you stay in the legal ranges for the time parts this should work, i.e. it doesn't return 1234:35 as hours are <= 23.
maybe:
>>> import datetime
>>> dt0 = datetime.datetime(1,1,1)
>>> td = datetime.timedelta(minutes=34, hours=12, seconds=56)
>>> (dt0+td).strftime('%X')
'12:34:56'
>>> (dt0+td).strftime('%M:%S')
'34:56'
>>> (dt0+td).strftime('%H:%M')
'12:34'
>>>
I would seriously consider the Occam's Razor approach here:
td = str(timedelta).split('.')[0]
This returns a string without the microseconds
If you want to regenerate the datetime.timedelta object, just do this:
h,m,s = re.split(':', td)
new_delta = datetime.timedelta(hours=int(h),minutes=int(m),seconds=int(s))
2 years in, I love this language!
I used the humanfriendly python library to do this, it works very well.
import humanfriendly
from datetime import timedelta
delta = timedelta(seconds = 321)
humanfriendly.format_timespan(delta)
'5 minutes and 21 seconds'
Available at https://pypi.org/project/humanfriendly/
Questioner wants a nicer format than the typical:
>>> import datetime
>>> datetime.timedelta(seconds=41000)
datetime.timedelta(0, 41000)
>>> str(datetime.timedelta(seconds=41000))
'11:23:20'
>>> str(datetime.timedelta(seconds=4102.33))
'1:08:22.330000'
>>> str(datetime.timedelta(seconds=413302.33))
'4 days, 18:48:22.330000'
So, really there's two formats, one where days are 0 and it's left out, and another where there's text "n days, h:m:s". But, the seconds may have fractions, and there's no leading zeroes in the printouts, so columns are messy.
Here's my routine, if you like it:
def printNiceTimeDelta(stime, etime):
delay = datetime.timedelta(seconds=(etime - stime))
if (delay.days > 0):
out = str(delay).replace(" days, ", ":")
else:
out = "0:" + str(delay)
outAr = out.split(':')
outAr = ["%02d" % (int(float(x))) for x in outAr]
out = ":".join(outAr)
return out
this returns output as dd:hh:mm:ss format:
00:00:00:15
00:00:00:19
02:01:31:40
02:01:32:22
I did think about adding years to this, but this is left as an exercise for the reader, since the output is safe at over 1 year:
>>> str(datetime.timedelta(seconds=99999999))
'1157 days, 9:46:39'
My datetime.timedelta objects went greater than a day. So here is a further problem. All the discussion above assumes less than a day. A timedelta is actually a tuple of days, seconds and microseconds. The above discussion should use td.seconds as joe did, but if you have days it is NOT included in the seconds value.
I am getting a span of time between 2 datetimes and printing days and hours.
span = currentdt - previousdt
print '%d,%d\n' % (span.days,span.seconds/3600)
I have a function:
def period(delta, pattern):
d = {'d': delta.days}
d['h'], rem = divmod(delta.seconds, 3600)
d['m'], d['s'] = divmod(rem, 60)
return pattern.format(**d)
Examples:
>>> td = timedelta(seconds=123456789)
>>> period(td, "{d} days {h}:{m}:{s}")
'1428 days 21:33:9'
>>> period(td, "{h} hours, {m} minutes and {s} seconds, {d} days")
'21 hours, 33 minutes and 9 seconds, 1428 days'
Following Joe's example value above, I'd use the modulus arithmetic operator, thusly:
td = datetime.timedelta(hours=10.56)
td_str = "%d:%d" % (td.seconds/3600, td.seconds%3600/60)
Note that integer division in Python rounds down by default; if you want to be more explicit, use math.floor() or math.ceil() as appropriate.
One liner. Since timedeltas do not offer datetime's strftime, bring the timedelta back to a datetime, and use stftime.
This can not only achieve the OP's requested format Hours:Minutes, now you can leverage the full formatting power of datetime's strftime, should your requirements change to another representation.
import datetime
td = datetime.timedelta(hours=2, minutes=10, seconds=5)
print(td)
print(datetime.datetime.strftime(datetime.datetime.strptime(str(td), "%H:%M:%S"), "%H:%M"))
Output:
2:10:05
02:10
This also solves the annoyance that timedeltas are formatted into strings as H:MM:SS rather than HH:MM:SS, which lead me to this problem, and the solution I've shared.
import datetime
hours = datetime.timedelta(hours=16, minutes=30)
print((datetime.datetime(1,1,1) + hours).strftime('%H:%M'))
def seconds_to_time_left_string(total_seconds):
s = int(total_seconds)
years = s // 31104000
if years > 1:
return '%d years' % years
s = s - (years * 31104000)
months = s // 2592000
if years == 1:
r = 'one year'
if months > 0:
r += ' and %d months' % months
return r
if months > 1:
return '%d months' % months
s = s - (months * 2592000)
days = s // 86400
if months == 1:
r = 'one month'
if days > 0:
r += ' and %d days' % days
return r
if days > 1:
return '%d days' % days
s = s - (days * 86400)
hours = s // 3600
if days == 1:
r = 'one day'
if hours > 0:
r += ' and %d hours' % hours
return r
s = s - (hours * 3600)
minutes = s // 60
seconds = s - (minutes * 60)
if hours >= 6:
return '%d hours' % hours
if hours >= 1:
r = '%d hours' % hours
if hours == 1:
r = 'one hour'
if minutes > 0:
r += ' and %d minutes' % minutes
return r
if minutes == 1:
r = 'one minute'
if seconds > 0:
r += ' and %d seconds' % seconds
return r
if minutes == 0:
return '%d seconds' % seconds
if seconds == 0:
return '%d minutes' % minutes
return '%d minutes and %d seconds' % (minutes, seconds)
for i in range(10):
print pow(8, i), seconds_to_time_left_string(pow(8, i))
Output:
1 1 seconds
8 8 seconds
64 one minute and 4 seconds
512 8 minutes and 32 seconds
4096 one hour and 8 minutes
32768 9 hours
262144 3 days
2097152 24 days
16777216 6 months
134217728 4 years
I had a similar problem with the output of overtime calculation at work. The value should always show up in HH:MM, even when it is greater than one day and the value can get negative. I combined some of the shown solutions and maybe someone else find this solution useful. I realized that if the timedelta value is negative most of the shown solutions with the divmod method doesn't work out of the box:
def td2HHMMstr(td):
'''Convert timedelta objects to a HH:MM string with (+/-) sign'''
if td < datetime.timedelta(seconds=0):
sign='-'
td = -td
else:
sign = ''
tdhours, rem = divmod(td.total_seconds(), 3600)
tdminutes, rem = divmod(rem, 60)
tdstr = '{}{:}:{:02d}'.format(sign, int(tdhours), int(tdminutes))
return tdstr
timedelta to HH:MM string:
td2HHMMstr(datetime.timedelta(hours=1, minutes=45))
'1:54'
td2HHMMstr(datetime.timedelta(days=2, hours=3, minutes=2))
'51:02'
td2HHMMstr(datetime.timedelta(hours=-3, minutes=-2))
'-3:02'
td2HHMMstr(datetime.timedelta(days=-35, hours=-3, minutes=-2))
'-843:02'
from django.utils.translation import ngettext
def localize_timedelta(delta):
ret = []
num_years = int(delta.days / 365)
if num_years > 0:
delta -= timedelta(days=num_years * 365)
ret.append(ngettext('%d year', '%d years', num_years) % num_years)
if delta.days > 0:
ret.append(ngettext('%d day', '%d days', delta.days) % delta.days)
num_hours = int(delta.seconds / 3600)
if num_hours > 0:
delta -= timedelta(hours=num_hours)
ret.append(ngettext('%d hour', '%d hours', num_hours) % num_hours)
num_minutes = int(delta.seconds / 60)
if num_minutes > 0:
ret.append(ngettext('%d minute', '%d minutes', num_minutes) % num_minutes)
return ' '.join(ret)
This will produce:
>>> from datetime import timedelta
>>> localize_timedelta(timedelta(days=3660, minutes=500))
'10 years 10 days 8 hours 20 minutes'
A straight forward template filter for this problem. The built-in function int() never rounds up. F-Strings (i.e. f'') require python 3.6.
#app_template_filter()
def diffTime(end, start):
diff = (end - start).total_seconds()
d = int(diff / 86400)
h = int((diff - (d * 86400)) / 3600)
m = int((diff - (d * 86400 + h * 3600)) / 60)
s = int((diff - (d * 86400 + h * 3600 + m *60)))
if d > 0:
fdiff = f'{d}d {h}h {m}m {s}s'
elif h > 0:
fdiff = f'{h}h {m}m {s}s'
elif m > 0:
fdiff = f'{m}m {s}s'
else:
fdiff = f'{s}s'
return fdiff
If you happen to have IPython in your packages (you should), it has (up to now, anyway) a very nice formatter for durations (in float seconds). That is used in various places, for example by the %%time cell magic. I like the format it produces for short durations:
>>> from IPython.core.magics.execution import _format_time
>>>
>>> for v in range(-9, 10, 2):
... dt = 1.25 * 10**v
... print(_format_time(dt))
1.25 ns
125 ns
12.5 µs
1.25 ms
125 ms
12.5 s
20min 50s
1d 10h 43min 20s
144d 16h 13min 20s
14467d 14h 13min 20s
I continued from MarredCheese's answer and added year, month, millicesond and microsecond
all numbers are formatted to integer except for second, thus the fraction of a second can be customized.
#kfmfe04 asked for fraction of a second so I posted this solution
In the main there are some examples.
from string import Formatter
from datetime import timedelta
def strfdelta(tdelta, fmt='{D:02}d {H:02}h {M:02}m {S:02.0f}s', inputtype='timedelta'):
"""Convert a datetime.timedelta object or a regular number to a custom-
formatted string, just like the stftime() method does for datetime.datetime
objects.
The fmt argument allows custom formatting to be specified. Fields can
include seconds, minutes, hours, days, and weeks. Each field is optional.
Some examples:
'{D:02}d {H:02}h {M:02}m {S:02.0f}s' --> '05d 08h 04m 02s' (default)
'{W}w {D}d {H}:{M:02}:{S:02.0f}' --> '4w 5d 8:04:02'
'{D:2}d {H:2}:{M:02}:{S:02.0f}' --> ' 5d 8:04:02'
'{H}h {S:.0f}s' --> '72h 800s'
The inputtype argument allows tdelta to be a regular number instead of the
default, which is a datetime.timedelta object. Valid inputtype strings:
's', 'seconds',
'm', 'minutes',
'h', 'hours',
'd', 'days',
'w', 'weeks'
"""
# Convert tdelta to integer seconds.
if inputtype == 'timedelta':
remainder = tdelta.total_seconds()
elif inputtype in ['s', 'seconds']:
remainder = float(tdelta)
elif inputtype in ['m', 'minutes']:
remainder = float(tdelta)*60
elif inputtype in ['h', 'hours']:
remainder = float(tdelta)*3600
elif inputtype in ['d', 'days']:
remainder = float(tdelta)*86400
elif inputtype in ['w', 'weeks']:
remainder = float(tdelta)*604800
f = Formatter()
desired_fields = [field_tuple[1] for field_tuple in f.parse(fmt)]
possible_fields = ('Y','m','W', 'D', 'H', 'M', 'S', 'mS', 'µS')
constants = {'Y':86400*365.24,'m': 86400*30.44 ,'W': 604800, 'D': 86400, 'H': 3600, 'M': 60, 'S': 1, 'mS': 1/pow(10,3) , 'µS':1/pow(10,6)}
values = {}
for field in possible_fields:
if field in desired_fields and field in constants:
Quotient, remainder = divmod(remainder, constants[field])
values[field] = int(Quotient) if field != 'S' else Quotient + remainder
return f.format(fmt, **values)
if __name__ == "__main__":
td = timedelta(days=717, hours=3, minutes=5, seconds=8, microseconds=3549)
print(strfdelta(td,'{Y} years {m} months {W} weeks {D} days {H:02}:{M:02}:{S:02}'))
print(strfdelta(td,'{m} months {W} weeks {D} days {H:02}:{M:02}:{S:02.4f}'))
td = timedelta( seconds=8, microseconds=8549)
print(strfdelta(td,'{S} seconds {mS} milliseconds {µS} microseconds'))
print(strfdelta(td,'{S:.0f} seconds {mS} milliseconds {µS} microseconds'))
print(strfdelta(pow(10,7),inputtype='s'))
Output:
1 years 11 months 2 weeks 3 days 01:09:56.00354900211096
23 months 2 weeks 3 days 00:12:20.0035
8.008549 seconds 8 milliseconds 549 microseconds
8 seconds 8 milliseconds 549 microseconds
115d 17h 46m 40s
Here's a function to stringify timedelta.total_seconds(). It works in python 2 and 3.
def strf_interval(seconds):
days, remainder = divmod(seconds, 86400)
hours, remainder = divmod(remainder, 3600)
minutes, seconds = divmod(remainder, 60)
return '{} {} {} {}'.format(
"" if int(days) == 0 else str(int(days)) + ' days',
"" if int(hours) == 0 else str(int(hours)) + ' hours',
"" if int(minutes) == 0 else str(int(minutes)) + ' mins',
"" if int(seconds) == 0 else str(int(seconds)) + ' secs'
)
Example output:
>>> print(strf_interval(1))
1 secs
>>> print(strf_interval(100))
1 mins 40 secs
>>> print(strf_interval(1000))
16 mins 40 secs
>>> print(strf_interval(10000))
2 hours 46 mins 40 secs
>>> print(strf_interval(100000))
1 days 3 hours 46 mins 40 secs
timedelta to string, use for print running time info.
def strfdelta_round(tdelta, round_period='second'):
"""timedelta to string, use for measure running time
attend period from days downto smaller period, round to minimum period
omit zero value period
"""
period_names = ('day', 'hour', 'minute', 'second', 'millisecond')
if round_period not in period_names:
raise Exception(f'round_period "{round_period}" invalid, should be one of {",".join(period_names)}')
period_seconds = (86400, 3600, 60, 1, 1/pow(10,3))
period_desc = ('days', 'hours', 'mins', 'secs', 'msecs')
round_i = period_names.index(round_period)
s = ''
remainder = tdelta.total_seconds()
for i in range(len(period_names)):
q, remainder = divmod(remainder, period_seconds[i])
if int(q)>0:
if not len(s)==0:
s += ' '
s += f'{q:.0f} {period_desc[i]}'
if i==round_i:
break
if i==round_i+1:
s += f'{remainder} {period_desc[round_i]}'
break
return s
e.g. auto omit zero leading period:
>>> td = timedelta(days=0, hours=2, minutes=5, seconds=8, microseconds=3549)
>>> strfdelta_round(td, 'second')
'2 hours 5 mins 8 secs'
or omit middle zero period:
>>> td = timedelta(days=2, hours=0, minutes=5, seconds=8, microseconds=3549)
>>> strfdelta_round(td, 'millisecond')
'2 days 5 mins 8 secs 3 msecs'
or round to minutes, omit below minutes:
>>> td = timedelta(days=1, hours=2, minutes=5, seconds=8, microseconds=3549)
>>> strfdelta_round(td, 'minute')
'1 days 2 hours 5 mins'
Please check this function - it converts timedelta object into string 'HH:MM:SS'
def format_timedelta(td):
hours, remainder = divmod(td.total_seconds(), 3600)
minutes, seconds = divmod(remainder, 60)
hours, minutes, seconds = int(hours), int(minutes), int(seconds)
if hours < 10:
hours = '0%s' % int(hours)
if minutes < 10:
minutes = '0%s' % minutes
if seconds < 10:
seconds = '0%s' % seconds
return '%s:%s:%s' % (hours, minutes, seconds)
If you already have a timedelta obj then just convert that obj into string. Remove the last 3 characters of the string and print. This will truncate the seconds part and print the rest of it in the format Hours:Minutes.
t = str(timedeltaobj)
print t[:-3]
I wanted to do this so wrote a simple function. It works great for me and is quite versatile (supports years to microseconds, and any granularity level, e.g. you can pick between '2 days, 4 hours, 48 minutes' and '2 days, 4 hours' and '2 days, 4.8 hours', etc.
def pretty_print_timedelta(t, max_components=None, max_decimal_places=2):
'''
Print a pretty string for a timedelta.
For example datetime.timedelta(days=2, seconds=17280) will be printed as '2 days, 4 hours, 48 minutes'. Setting max_components to e.g. 1 will change this to '2.2 days', where the
number of decimal points can also be set.
'''
time_scales = [timedelta(days=365), timedelta(days=1), timedelta(hours=1), timedelta(minutes=1), timedelta(seconds=1), timedelta(microseconds=1000), timedelta(microseconds=1)]
time_scale_names_dict = {timedelta(days=365): 'year',
timedelta(days=1): 'day',
timedelta(hours=1): 'hour',
timedelta(minutes=1): 'minute',
timedelta(seconds=1): 'second',
timedelta(microseconds=1000): 'millisecond',
timedelta(microseconds=1): 'microsecond'}
count = 0
txt = ''
first = True
for scale in time_scales:
if t >= scale:
count += 1
if count == max_components:
n = t / scale
else:
n = int(t / scale)
t -= n*scale
n_txt = str(round(n, max_decimal_places))
if n_txt[-2:]=='.0': n_txt = n_txt[:-2]
txt += '{}{} {}{}'.format('' if first else ', ', n_txt, time_scale_names_dict[scale], 's' if n>1 else '', )
if first:
first = False
if len(txt) == 0:
txt = 'none'
return txt
I had the same problem and I am using pandas Timedeltas, didn't want to bring in additional dependencies (another answer mentions humanfriendly) so I wrote this small function to print out only the relevant information:
def format_timedelta(td: pd.Timedelta) -> str:
if pd.isnull(td):
return str(td)
else:
c = td.components._asdict()
return ", ".join(f"{n} {unit}" for unit, n in c.items() if n)
For example, pd.Timedelta(hours=3, seconds=12) would print as 3 hours, 12 seconds.
I suggest the following method so that we can utilize the standard formatting function, pandas.Timestamp.strftime!
from pandas import Timestamp, Timedelta
(Timedelta("2 hours 30 min") + Timestamp("00:00:00")).strftime("%H:%M")

Natural time interval processing in Python

I am wondering how to take a user-inputted string (i.e. 1 day, 5 hours, 15 minutes, 2 seconds) and convert it to either a timedelta object or (preferably) the number of seconds in that interval.
Note that:
This is not a question about datetimes, it is about timedeltas. I don’t need “Tomorrow” or “In 5 minutes”, I need “1 day” or “5 minutes.”
All fields are optional
These are the possible fields:
year, years, or y
month, months, or m
week, weeks, or w
day, days, or d
hour, hours, or h
minute, minutes, or m
second, seconds, or s
If you can get me started, I can probably do the rest
The input can either be delimited by , or whitespace
Thank you!
You could use parsedatetime module:
#!/usr/bin/env python
from datetime import date, datetime
import parsedatetime as pdt # $ pip install parsedatetime
cal = pdt.Calendar()
midnight = datetime.fromordinal(date.today().toordinal())
for s in "1 day, 5 hours, 15 minutes, 2 seconds".split(', '):
print(repr(cal.parseDT(s, midnight)[0] - midnight))
Output
datetime.timedelta(1)
datetime.timedelta(0, 18000)
datetime.timedelta(0, 900)
datetime.timedelta(0, 2)
To get number of seconds, call .total_seconds() or if you don't need fractions of a second; you could truncate it:
integer_seconds = td // timedelta(seconds=1)
Thank you #y0prst for the answer!
Here it is, converted to a program:
import re, datetime
def get_seconds(text):
splitted_input = filter(None, re.split('[, ]', text))
assert len(splitted_input) % 2 == 0
grouped_input = zip(*(iter(splitted_input),) * 2)
# ⬆︎ This is tricky; see https://stackoverflow.com/questions/1624883/alternative-way-to-split-a-list-into-groups-of-n
kwargs = {
'year':0,
'month':0,
'day':0,
'hour':0,
'minute':0,
'second':0,
'microsecond':0,
}
for n, unit in grouped_input:
n = int(n)
if unit.startswith('y'):
kwargs['year'] += n
elif unit.startswith('mo'):
kwargs['month'] += n
elif unit.startswith('w'):
kwargs['day'] += 7*n
elif unit.startswith('d'):
kwargs['day'] += n
elif unit.startswith('h'):
kwargs['hour'] += n
elif unit.startswith('m'):
kwargs['minute'] += n
elif unit.startswith('s'):
kwargs['second'] += n
else:
assert False, unit
for k, v in kwargs:
kwargs[k] += getattr(now, k)
now = datetime.datetime.now()
return (datetime.datetime(**kwargs) - now).total_seconds()

How to get total hours and minutes for timedelta in Python

How do I return or turn a timedelta, which is bigger than 24 hours, into an object containing the total hours and minutes (for example, 26:30) instead of "1 day, 2:30"?
You can use total_seconds() to compute the number of seconds. This can then be turned into minutes or hours:
>>> datetime.timedelta(days=3).total_seconds()
259200.0
Completing the answer of Visser using timedelta.total_seconds() :
import datetime
duration = datetime.timedelta(days = 2, hours = 4, minutes = 15)
Once we got a timedelta object:
totsec = duration.total_seconds()
h = totsec//3600
m = (totsec%3600) // 60
sec =(totsec%3600)%60 #just for reference
print "%d:%d" %(h,m)
Out: 52:15
offset_seconds = timedelta.total_seconds()
if offset_seconds < 0:
sign = "-"
else:
sign = "+"
# we will prepend the sign while formatting
if offset_seconds < 0:
offset_seconds *= -1
offset_hours = offset_seconds / 3600.0
offset_minutes = (offset_hours % 1) * 60
offset = "{:02d}:{:02d}".format(int(offset_hours), int(offset_minutes))
offset = sign + offset

Convert a datetime.timedelta into ISO 8601 duration in Python?

Given a datetime.timedelta, how to convert it into an ISO 8601 duration string?
For example, given datetime.timedelta(0, 18, 179651), how do I get 'PT18.179651S'?
For the reverse, see Is there an easy way to convert ISO 8601 duration to timedelta?.
Although the datetime module contains an implementation for a ISO 8601 notation for datetime or date objects, it does not currently (Python 3.7) support the same for timedelta objects. However, the isodate module (pypi link) has functionality to generate a duration string in ISO 8601 notation:
In [15]: import isodate, datetime
In [16]: print(isodate.duration_isoformat(datetime.datetime.now() - datetime.datetime(1985, 8, 13, 15)))
P12148DT4H20M39.47017S
which means 12148 days, 4 hours, 20 minutes, 39.47017 seconds.
This is a function from Tin Can Python project (Apache License 2.0) that can do the conversion:
def iso8601(value):
# split seconds to larger units
seconds = value.total_seconds()
minutes, seconds = divmod(seconds, 60)
hours, minutes = divmod(minutes, 60)
days, hours = divmod(hours, 24)
days, hours, minutes = map(int, (days, hours, minutes))
seconds = round(seconds, 6)
## build date
date = ''
if days:
date = '%sD' % days
## build time
time = u'T'
# hours
bigger_exists = date or hours
if bigger_exists:
time += '{:02}H'.format(hours)
# minutes
bigger_exists = bigger_exists or minutes
if bigger_exists:
time += '{:02}M'.format(minutes)
# seconds
if seconds.is_integer():
seconds = '{:02}'.format(int(seconds))
else:
# 9 chars long w/leading 0, 6 digits after decimal
seconds = '%09.6f' % seconds
# remove trailing zeros
seconds = seconds.rstrip('0')
time += '{}S'.format(seconds)
return u'P' + date + time
E.g.
>>> iso8601(datetime.timedelta(0, 18, 179651))
'PT18.179651S'
I tried to write a shorter function:
def iso8601(tdelta):
ts = tdelta.total_seconds()
d = int(ts // 86400)
s = round(ts % 60, 6)
hms = int(ts // 3600 % 24), int(ts // 60 % 60), s if s % 1 != 0 else int(s)
t = ''.join([str(p[0]) + p[1] for p in zip(hms, ['H', 'M', 'S']) if p[0]])
sep = 'T' if any(hms) else ''
return 'P' + (str(d) + 'D' if d else '') + sep + (t if ts else 'T0S')
E.g.
>>> iso8601(datetime.timedelta(0, 18, 179651))
'PT18.179651S'
This may be less readable for some, but I think it's easier to take it apart and inline it in certain use cases. For example, if you're not using timedelta but already have the duration in integer seconds ts and, say, your durations are always shorter than a day, this becomes:
hms = ts // 3600, ts // 60 % 60, ts % 60
t = ''.join([str(p[0]) + p[1] for p in zip(hms, ['H', 'M', 'S']) if p[0]])
ts_iso8601 = 'PT' + t if ts else 'PT0S'

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