What's the difference between chill hours and the existing cooling-days, except for the value of the base?
On Tue, Jan 18, 2022 at 3:47 PM Seth Ratner <[email protected]> wrote: > Ok, I'm looking at this from a different angle, and was wondering if > someone knew the "right" way to do this before I go inventing a more > complicated solution. > > For Chill Hours, I just need to add up the time that the temp is below XX > degrees between two dates. As I understand WeeWX, every database entry has > the interval length and the average temp for that interval. So in theory I > can query the DB for the number of entries between two timestamps where the > temp is below XX, and multiply the number of entries by the interval > duration (5 minutes default). > > However, that would have me doing that query every time I wanted to > display the value, which might be unnecessary processing power. It would > also limit my display options. For example, if I wanted a chart to show > chill hours the same way rain can be shown (with a cumulative line, an > absolute line, etc), I'd have to come up with a more complicated query. > > Which got me thinking, chill hours are somewhat similar to rain, in that > they are additive. So do I just create a service that gets triggered on an > archive entry, looks at the temp for that archive entry, and if the temp is > below the threshold it adds a value to column 'chill_hours' equal to the > interval duration is? Then instead of inches, I'm using "minutes" as the > unit of measurement. > > And is there any way to influence the daily summary table that would be > created for this new "chill hours" field? Or do they all have to follow the > same logic? > > Am I going about this the entirely wrong way? Ultimately I'd like to > create the ability to track the accumulated hours of various custom temp > ranges, and use that data for charting similar to other existing fields. > > Thanks, > Seth > > > > > > On Saturday, December 25, 2021 at 11:48:43 AM UTC-6 Seth Ratner wrote: > >> Hi everyone, >> >> I was wondering if anyone had already come up with a way to monitor chill >> hours (cumulative hours below 45℉) in WeeWx. I'm using Belchertown, and it >> would be nice to have a readout with Oct-May chill hours, and maybe a chart >> that shows the per-week and cumulative hours together. >> >> Thanks! >> Seth >> > -- > You received this message because you are subscribed to the Google Groups > "weewx-user" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/weewx-user/dcff6386-f236-43ab-92e2-c2e0c76acd37n%40googlegroups.com > <https://groups.google.com/d/msgid/weewx-user/dcff6386-f236-43ab-92e2-c2e0c76acd37n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/weewx-user/CAPq0zEDVkLD4MSnWOiFJ1bMJ52XsgfOVAmetDkLYbJiiAEN5dQ%40mail.gmail.com.
