Standard "fence post" math. :-) On Mon, Sep 2, 2019 at 5:42 PM Pat <p...@obrienphoto.net> wrote:
> I don't know why, but I'm fascinated with this small bit of code. I always > wondered how the archive interval runs on the 5th minute reliably (on a > vanilla install). It doesn't matter when you start weewx, it'll run on that > 5th minute interval. If I start weewx at 8:31, I'll get an archive (most > times) at 8:35. That got me thinking it's not a sleep, but something else. > > So I dug and I found the magic timer a few months ago > <https://github.com/weewx/weewx/blob/master/bin/weewx/engine.py#L531>, > but I've been stuck on trying to understand the math behind it. Is someone > able to explain this in laymans terms? > > Let's say these are the variables: > > int(self.engine._get_console_time() = 1567470965 > self.archive_interval = 300 > > If I take a the console time (1567470965), divide it by 300, I get 5224903 > Then adding 1 is easy, I get 5224904 > Then multiplying this by 300 gives me the time ahead on the 5th minute, > or 1567471200 > > I have no idea how or why that +1 alters the end result. It's just adding > a second to the timestamp. > > (int( 1567470965 / 300) + 1) * 300 = 1567471200 > > I think it's pretty cool how this works! > > -- > You received this message because you are subscribed to the Google Groups > "weewx-development" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to weewx-development+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/weewx-development/9c929337-f1ae-4034-a18f-c7191472fb13%40googlegroups.com > <https://groups.google.com/d/msgid/weewx-development/9c929337-f1ae-4034-a18f-c7191472fb13%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "weewx-development" group. To unsubscribe from this group and stop receiving emails from it, send an email to weewx-development+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/weewx-development/CAPq0zEA9Fqof6Zs34%2B40%2B0QaGTAM4YfbfDrGoXo_kmdb1kryLw%40mail.gmail.com.
