kpp9c wrote:
> Hi,
>
> I was looking at python & datetime and hoping that it would already
> have
> a method/func to translate time formats. I need to translate seconds
> to hh:mm:ss.ms and vice versa and would like the ability to do some
> basic arithmetic in these formats. I think that there just has to be a
> package
> or module out there that already does this with reasonable speed and
> accuracy.
>
> Sadly, i do indeed need both reasonable speed and accuracy since i
> will be adding up huge masses of small events (around 10 to 60 ms
> milliseconds
> in length) to create cloud like textures for real time audio/video at
> high sampling rates.
>
> i googled for hh:mm:ss.ms + python and didn't find much...
>
> best,
>
> -kp---
>
> [mac os x w/ python 2.4.1]
Hmmm ... not difficult to do, but it's the "speed" bit that's tricky.
Here's quick and dirty implementation, but I wouldn't place any bets on
it being fast (or accurate enough for that matter!)
#!/bin/env python
# vim: set noet sw=4 ts=4:
import datetime
def secs2time(s):
ms = int((s - int(s)) * 1000000)
s = int(s)
# Get rid of this line if s will never exceed 86400
while s >= 24*60*60: s -= 24*60*60
h = s / (60*60)
s -= h*60*60
m = s / 60
s -= m*60
return datetime.time(h, m, s, ms)
def time2secs(d):
return d.hour*60*60 + d.minute*60 + d.second + \
(float(d.microsecond) / 1000000)
if __name__ == "__main__":
for i in (80000.123, 0.0, 5873, 12345.6789):
print "%12.6f -> %15s -> %12.6f" % (
i,
secs2time(i),
time2secs(secs2time(i))
)
assert i == time2secs(secs2time(i))
from timeit import Timer
timer = Timer(
setup="from __main__ import time2secs, secs2time",
stmt="time2secs(secs2time(12345.6789))")
count = 1000000
total = timer.timeit(count)
print "Time for %d invocations: %.10fs" % (count, total)
print "Time per invocation: %.10fs" % (total / count,)
And the output:
80000.123000 -> 22:13:20.123000 -> 80000.123000
0.000000 -> 00:00:00 -> 0.000000
5873.000000 -> 01:37:53 -> 5873.000000
12345.678900 -> 03:25:45.678900 -> 12345.678900
Time for 1000000 invocations: 9.3959178925s
Time per invocation: 0.0000093959s
Huh ... what d'ya know ... good thing I ain't a betting man!
Dave.
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