simpler increment of time values?

Chris Angelico rosuav at gmail.com
Thu Jul 5 13:16:16 EDT 2012


On Fri, Jul 6, 2012 at 3:06 AM, Ian Kelly <ian.g.kelly at gmail.com> wrote:
> The "+ 86400" is redundant; you'll get the same answer with or without
> it.  There is nothing to fear from going negative when doing modulo
> arithmetic, because unlike C, Python actually has well-defined
> semantics regarding modulo division of negative numbers.
>
>>>> (13382 + 86400 - 42597) % 86400
> 57185
>>>> (13382 - 42597) % 86400
> 57185

Ah good. There's a lot of languages like that these days, but I've
gotten so into the habit of not depending on it that I just
automatically add N first. It's redundant but insignificant.

So it's even easier than I said. And bonus lesson for the day: Try
things in the interactive interpreter before you post. :)

ChrisA



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