Velocity Reviews > Time travel

# Time travel

Lee Merrill
Guest
Posts: n/a

 11-17-2009
I'm seeing an anomaly in the python time function on March 9, 2008
(the "spring foward" time):

>>> time.mktime((2008, 3, 9, 2, 59, 59, 0, 0, -1))

1205049599.0
>>> time.mktime((2008, 3, 9, 3, 0, 0, 0, 0, -1))

1205046000.0

Does anyone have an idea as to what might cause a 4000 seconds
backwards jump on March 9th of last year? I would have expected 3600
seconds.

Thanks,
Lee

P.S. A full program demonstrating the question:

#!/usr/bin/env python

import time, datetime

d1 = datetime.datetime(2008, 3, 9, 2, 59, 0).timetuple()
#!/usr/bin/env python

import time, datetime

d1 = datetime.datetime(2008, 3, 9, 2, 59, 0).timetuple()
d2 = datetime.datetime(2008, 3, 9, 3, 0, 0).timetuple()
t1 = time.mktime(d1)
t2 = time.mktime(d2)

print t1, t2

Lee Merrill
Guest
Posts: n/a

 11-17-2009
And I can't do arithmetic, it is actually about 3600--never mind!

On Nov 17, 10:37*am, Lee Merrill <(E-Mail Removed)> wrote:
> I'm seeing an anomaly in the python time function on March 9, 2008
> (the "spring foward" time):
>
> >>> time.mktime((2008, 3, 9, 2, 59, 59, 0, 0, -1))

> 1205049599.0
> >>> time.mktime((2008, 3, 9, 3, 0, 0, 0, 0, -1))

>
> 1205046000.0
>
> Does anyone have an idea as to what might cause a 4000 seconds
> backwards jump on March 9th of last year? I would have expected 3600
> seconds.
>
> Thanks,
> Lee
>
> P.S. A full program demonstrating the question:
>
> #!/usr/bin/env python
>
> import time, datetime
>
> d1 = datetime.datetime(2008, 3, 9, 2, 59, 0).timetuple()
> #!/usr/bin/env python
>
> import time, datetime
>
> d1 = datetime.datetime(2008, 3, 9, 2, 59, 0).timetuple()
> d2 = datetime.datetime(2008, 3, 9, 3, 0, 0).timetuple()
> t1 = time.mktime(d1)
> t2 = time.mktime(d2)
>
> print t1, t2

greg
Guest
Posts: n/a

 11-18-2009
Lee Merrill wrote:
> And I can't do arithmetic, it is actually about 3600--never mind!

Don't feel too bad. Obviously Guido nipped back to
March 8 2008 in his time machine and fixed the problem,
making it *look* like you can't do arithmetic. Time
travel often leads to embarrassments like that.

--
Greg