Thanks Tom I though you could only have one time delta for a trend ? So if I did week and could not have month or year ?
Cheers Michael On Wednesday, 29 November 2017 10:40:51 UTC+11, Tom Keffer wrote: > > Hello, Michael and welcome to WeeWX. > > Would it work if I did something like >> seven_day_stats1 = TimespanBinder .... >> seven_day_stats2 = TimespanBinder .... >> seven_day_stats = seven_day_stats1 - seven_day_stats2 > > > Unfortunately, no, because there is no subtraction operator defined for > type TimespanBinder. > > Why not just use the existing tag $trend > <http://weewx.com/docs/customizing.htm#_________Tag_$trend_______>? If > that's not what you had in mind, try hacking object TrendObj to get exactly > what you want. > > -tk > > > On Tue, Nov 28, 2017 at 5:17 PM, Michael Hornsby <[email protected] > <javascript:>> wrote: > >> Hi >> >> I'm migrating from wview and very excited with what can be done with >> weewx. At the moment I have php code and custom C code and I can see I can >> create a much better package with weewx. >> >> I'm trying to get my head around how a can construct a search list >> extension so I can find the change in a value from a week , month or year >> ago >> >> For example in a template I have this >> $week.outHumidity.avg.raw - $week($weeks_ago=1).outHumidity.avg.raw >> >> I want to know compared to last week / month / year whats the difference >> in the average temp , total rain etc >> >> I'm looking at the example below and thinking ok. So I need to run the >> stats for two periods and subtract them. >> >> >> week_dt = datetime.date.fromtimestamp(timespan.stop) - \ >> >> datetime.timedelta(weeks=1) >> # 5 >> # Convert it to unix epoch time: >> week_ts = time.mktime(week_dt.timetuple()) >> # 6 >> # Form a TimespanBinder object, using the time span we just >> # calculated: >> seven_day_stats = TimespanBinder(TimeSpan(week_ts, timespan.stop), >> db_lookup, >> formatter=self.generator.formatter, >> converter=self.generator.converter, >> skin_dict=self.generator.skin_dict) >> >> >> >> Would it work if I did something like >> >> seven_day_stats1 = TimespanBinder .... >> seven_day_stats2 = TimespanBinder .... >> >> seven_day_stats = seven_day_stats1 - seven_day_stats2 >> >> >> Thanks - I contributed a few features to wview. Hopefully I can do the >> same with weewx. >> >> Cheers >> Michael >> >> -- >> 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] <javascript:>. >> For more options, visit https://groups.google.com/d/optout. >> > > -- 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]. For more options, visit https://groups.google.com/d/optout.
