Using %f with strftime() in Python to get microseconds

问题

I'm trying to use strftime() to microsecond precision, which seems possible using %f (as stated here). However when I try the following code:

import time
import strftime from time

print strftime("%H:%M:%S.%f")

...I get the hour, the minutes and the seconds, but %f prints as %f, with no sign of the microseconds. I'm running Python 2.6.5 on Ubuntu, so it should be fine and %f should be supported (it's supported for 2.6 and above, as far as I know.)

回答1:

You can use datetime's strftime function to get this. The problem is that time's strftime accepts a timetuple that does not carry microsecond information.

from datetime import datetime
datetime.now().strftime("%H:%M:%S.%f")

Should do the trick!

回答2:

You are looking at the wrong documentation. The time module has different documentation.

You can use the datetime module strftime like this:

>>> from datetime import datetime
>>>
>>> now = datetime.now()
>>> now.strftime("%H:%M:%S.%f")
'12:19:40.948000'

回答3:

This should do the work

import datetime
datetime.datetime.now().strftime("%H:%M:%S.%f")

It will print

HH:MM:SS.microseconds like this e.g 14:38:19.425961

回答4:

With Python's time module you can't get microseconds with %f.

For those who still want to go with time module only, here is a workaround:

now = time.time()
mlsec = repr(now).split('.')[1][:3]
print time.strftime("%Y-%m-%d %H:%M:%S.{} %Z".format(mlsec), time.localtime(now))

You should get something like 2017-01-16 16:42:34.625 EET (yes, I use milliseconds as it's fairly enough).

To break the code into details, paste the below code into a Python console:

import time

# Get current timestamp
now = time.time()

# Debug now
now
print now
type(now)

# Debug strf time
struct_now = time.localtime(now)
print struct_now
type(struct_now)

# Print nicely formatted date
print time.strftime("%Y-%m-%d %H:%M:%S %Z", struct_now)

# Get miliseconds
mlsec = repr(now).split('.')[1][:3]
print mlsec

# Get your required timestamp string
timestamp = time.strftime("%Y-%m-%d %H:%M:%S.{} %Z".format(mlsec), struct_now)
print timestamp

For clarification purposes, I also paste my Python 2.7.12 result here:

>>> import time
>>> # get current timestamp
... now = time.time()
>>> # debug now
... now
1484578293.519106
>>> print now
1484578293.52
>>> type(now)
<type 'float'>
>>> # debug strf time
... struct_now = time.localtime(now)
>>> print struct_now
time.struct_time(tm_year=2017, tm_mon=1, tm_mday=16, tm_hour=16, tm_min=51, tm_sec=33, tm_wday=0, tm_yday=16, tm_isdst=0)
>>> type(struct_now)
<type 'time.struct_time'>
>>> # print nicely formatted date
... print time.strftime("%Y-%m-%d %H:%M:%S %Z", struct_now)
2017-01-16 16:51:33 EET
>>> # get miliseconds
... mlsec = repr(now).split('.')[1][:3]
>>> print mlsec
519
>>> # get your required timestamp string
... timestamp = time.strftime("%Y-%m-%d %H:%M:%S.{} %Z".format(mlsec), struct_now)
>>> print timestamp
2017-01-16 16:51:33.519 EET
>>>

回答5:

You can also get microsecond precision from the time module using its time() function.
(time.time() returns the time in seconds since epoch. Its fractional part is the time in microseconds, which is what you want.)

>>> from time import time
>>> time()
... 1310554308.287459   # the fractional part is what you want.


# comparision with strftime -
>>> from datetime import datetime
>>> from time import time
>>> datetime.now().strftime("%f"), time()
... ('287389', 1310554310.287459)

回答6:

When the "%f" for micro seconds isn't working, please use the following method:

import datetime

def getTimeStamp():
    dt = datetime.datetime.now()
    return dt.strftime("%Y%j%H%M%S") + str(dt.microsecond)

回答7:

If you want speed, try this:

def _timestamp(prec=0):
    t = time.time()
    s = time.strftime("%H:%M:%S", time.localtime(t))
    if prec > 0:
        s += ("%.9f" % (t % 1,))[1:2+prec]
    return s

Where prec is precision -- how many decimal places you want. Please note that the function does not have issues with leading zeros in fractional part like some other solutions presented here.

回答8:

If you want an integer, try this code:

import datetime
print(datetime.datetime.now().strftime("%s%f")[:13])

Output:

1545474382803

来源：https://stackoverflow.com/questions/6677332/using-f-with-strftime-in-python-to-get-microseconds

标签

python

time

strftime