我在格式化日期时间时遇到了麻烦。timedelta对象。
这就是我想做的: 我有一个对象列表，对象类的成员之一是显示事件持续时间的timedelta对象。我想以小时:分钟的格式显示这个持续时间。
我尝试了各种方法来做这件事，但我有困难。我目前的方法是为返回小时和分钟的对象在类中添加方法。我可以通过除以time得到小时数。秒乘以3600，四舍五入。我在得到剩余的秒并将其转换为分钟时遇到了麻烦。
顺便说一下，我使用谷歌AppEngine和Django模板来表示。
当前回答
下面是一个通用函数，用于将timedelta对象或常规数字(以秒或分钟等形式)转换为格式化良好的字符串。我采用了mpounsett对一个重复问题的出色回答，使其更加灵活，提高了可读性，并添加了文档。
你会发现这是迄今为止最灵活的答案，因为它允许你:
动态自定义字符串格式，而不是硬编码。 省略特定的时间间隔没有问题(参见下面的例子)。
功能:
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)
演示:
>>> 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
其他回答
如果您的包中碰巧有IPython(您应该)，那么它(到目前为止)有一个非常好的持续时间格式器(以浮点秒为单位)。它被用于许多地方，例如%%时间单元格魔法。我喜欢它在短时间内产生的格式:
>>> 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
谢谢大家的帮助。我把你的很多想法放在一起，让我知道你的想法。
我像这样在类中添加了两个方法:
def hours(self):
retval = ""
if self.totalTime:
hoursfloat = self.totalTime.seconds / 3600
retval = round(hoursfloat)
return retval
def minutes(self):
retval = ""
if self.totalTime:
minutesfloat = self.totalTime.seconds / 60
hoursAsMinutes = self.hours() * 60
retval = round(minutesfloat - hoursAsMinutes)
return retval
在我的django中，我使用了这个(sum是对象，它在一个字典中):
<td>{{ sum.0 }}</td>
<td>{{ sum.1.hours|stringformat:"d" }}:{{ sum.1.minutes|stringformat:"#02.0d" }}</td>
import datetime
hours = datetime.timedelta(hours=16, minutes=30)
print((datetime.datetime(1,1,1) + hours).strftime('%H:%M'))
>>> 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
将timedelta对象传递给str()函数调用的格式化代码与输入print td相同。因为你不想要秒，我们可以用冒号分隔字符串(3部分)，然后只用前2部分把它重新组合在一起。
下面是一个通用函数，用于将timedelta对象或常规数字(以秒或分钟等形式)转换为格式化良好的字符串。我采用了mpounsett对一个重复问题的出色回答，使其更加灵活，提高了可读性，并添加了文档。
你会发现这是迄今为止最灵活的答案，因为它允许你:
动态自定义字符串格式，而不是硬编码。 省略特定的时间间隔没有问题(参见下面的例子)。
功能:
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)
演示:
>>> 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
