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

# Format seconds to days, hours, minutes and seconds string
def ptime(seconds):
if(seconds >= 86400):
    d = seconds // 86400 # // floor division
    return (f"{round(d)}d") + ptime(seconds - d * 86400)
else:
    if(seconds >= 3600):
        h = seconds // 3600 
        return (f"{round(h)}h") + ptime(seconds - h * 3600)
    else:
        if(seconds >= 60):
            m = seconds // 60
            return(f"{round(m)}m" + ptime(seconds - m * 60))
        else:
            if (seconds > 0):
                return(f"{round(seconds)}s")
            else:
                return("")

其他回答

在这里,我会认真考虑奥卡姆剃刀方法:

td = str(timedelta).split('.')[0]

这将返回一个没有微秒的字符串

如果要重新生成datetime。Timedelta对象,只需要这样做:

h,m,s = re.split(':', td)
new_delta = datetime.timedelta(hours=int(h),minutes=int(m),seconds=int(s))

2年了,我爱上了这门语言!

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
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

一个班轮。由于timedelta不提供datetime的strftime,所以将timedelta带回datetime,并使用stftime。

这不仅可以实现OP要求的格式Hours:Minutes,现在您可以利用datetime的strftime的全部格式化功能,如果您的需求更改为另一种表示形式。

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

这也解决了时间增量被格式化为H:MM:SS而不是HH:MM:SS的字符串的烦恼,这导致了我的这个问题,以及我分享的解决方案。

我想这样做,所以写了一个简单的函数。它对我来说非常有用,而且非常通用(支持年到微秒,以及任何粒度级别,例如,你可以选择“2天4小时48分钟”和“2天4小时”和“2天4.8小时”等。

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