Converting date to milliseconds since 1-1-70

[NateM]

How do I convert any given date into a milliseconds value that
represents the number of milliseconds that have passed since January 1,
1970 00:00:00.000 GMT?
Is there an easy way to do this like Date in java?
Thanks,
Nate

[gry@ll.mit.edu]

Re: Converting date to milliseconds since 1-1-70

NateM wrote:[color=blue]
> How do I convert any given date into a milliseconds value that
> represents the number of milliseconds that have passed since January 1,
> 1970 00:00:00.000 GMT?
> Is there an easy way to do this like Date in java?
> Thanks,
> Nate[/color]

The main module for dates and times is "datetime"; so
[color=blue][color=green][color=darkred]
>>> import datetime
>>> t=datetime.date time.now()
>>> print t[/color][/color][/color]
2006-01-24 15:13:35.012755

To get at the "epoch" value, i.e. seconds since 1/1/1970, use the
"time" module:
[color=blue][color=green][color=darkred]
>>> import time
>>> print time.mktime(t.t imetuple())[/color][/color][/color]
1138133615.0

Now just add in the microseconds:[color=blue][color=green][color=darkred]
>>> epoch=time.mkti me(d.timetuple( ))+(t.microseco nd/1000000.)
>>> print epoch[/color][/color][/color]
1138133615.01

Use the "%" formatting operator to display more resolution:[color=blue][color=green][color=darkred]
>>> print '%f' % t[/color][/color][/color]
1138133615.0127 55

Note that the floating point division above is not exact and could
possibly
mangle the last digits.

Another way to this data is the datetime.strfti me member:
[color=blue][color=green][color=darkred]
>>> print d.strftime('%s. %%06d') % d.microsecond[/color][/color][/color]
'1138133615.012 755'

This gets you a string, not a number object. Converting the string to
a number again risks inaccuracy in the last digits:[color=blue][color=green][color=darkred]
>>> print float( '1138133615.012 755')[/color][/color][/color]
1138133615.0127 549

[NateM]

Re: Converting date to milliseconds since 1-1-70

Thank you! If I am reading in dates as strings from a text file, like
"5/11/1998", how do I convert that to a format I can pass into mktime?
Thanks again.

[Xavier Morel]

Re: Converting date to milliseconds since 1-1-70

NateM wrote:[color=blue]
> Thank you! If I am reading in dates as strings from a text file, like
> "5/11/1998", how do I convert that to a format I can pass into mktime?
> Thanks again.
>[/color]
Check time.strptime()