thanks Tom, I had thought about putting rain = prefer_software but as this type of rain configuration is not documented in the Weewx documentation (or at least I didn't find it!) I didn't take the initiative. .. stupid I am ! :-(
little suggestion Tom, perhaps it would be good to document this point in the [[Delta]] rain class? Well, not everyone is ignorant like me!! :-)) Many thanks to you for your help Tom Le dimanche 28 janvier 2024 à 00:21:43 UTC+1, Tom Keffer a écrit : > My apologies. I forgot one important detail. The "[Delta]" section tells > WeeWX how to calculate rain, but you also have to include "rain" under > [StdWXCalculations] / [[Calculations]] in order to get it to do the actual > calculation. It looks like > > [StdWXCalculate] > [[Calculations]] > ... > rain = prefer_hardware > > ... > [[Delta]] > [[[rain]]] > input = dayRain > > On Sat, Jan 27, 2024 at 9:17 AM Remy Lavabre <remy.l...@gmail.com> wrote: > >> Hello Tom, >> >> I followed your instructions: >> >> 1/“rain” field present in the database >> 2/ “dayRain” field not present in the database >> 3/ My driver returns “dayRain” values and not “rain” values in the >> packetsloop >> 4/ [[Delta]] [[ [rain]]] input = dayRain added in weewx.conf (under >> [StdWXCalculate]). >> >> I did some tests : my driver returns 0.0 for dayRain but unfortunately >> the "rain" field in my database always remains NULL, even after several >> recordings in weewx.conf. >> Shouldn't "rain" field go to 0.0? >> >> THANKS >> >> Le vendredi 26 janvier 2024 à 22:48:03 UTC+1, Tom Keffer a écrit : >> >>> If an observation type never gets reset to zero, you have two choices. >>> 1. Save the value. If you want to know daily use, take the difference of >>> the value. >>> 2. Save the difference. That is, the change in the value over an archive >>> period. If you want to know daily use, you would sum all the small deltas. >>> This is like rain >>> >>> See the discussion *Accumulated vs delta energy >>> <https://github.com/tkeffer/weewx-brultech?tab=readme-ov-file#accumulated-vs-delta-energy>* >>> in >>> the README of the Brultech driver for the pros and cons of the two >>> approaches. >>> >>> It is not necessary to save "dayRain". WeeWX mostly uses "rain". >>> Besides, as you note, it can always be calculated. >>> >>> >>> >>> On Fri, Jan 26, 2024 at 7:06 AM Remy Lavabre <remy.l...@gmail.com> >>> wrote: >>> >>>> And one more question.... >>>> Is it absolutely necessary to create a "dayRain" field in addition to >>>> the "rain" field in the weewx.sdb database? >>>> If the database only contains the [rain] field but the Weewx driver >>>> returns a "dayRain" field (cumulative rain over 24 hours since midnight) >>>> with a real value in each packetloop, the class [[Delta]] [[ [rain]]] >>>> input >>>> = dayRain will it work?? >>>> (the accumulation of rain since midnight is useless to me in a database >>>> field since it is easily calculated) >>>> Sorry for all the questions...and thanks again! ;-) >>>> >>>> Le vendredi 26 janvier 2024 à 15:46:04 UTC+1, Remy Lavabre a écrit : >>>> >>>>> Hello Tom and thank you for your response. >>>>> >>>>> [StdWXCalculate] >>>>> [[Calculations]] >>>>> ... >>>>> [[Delta]] >>>>> [[[rain]]] >>>>> input = dayRain >>>>> >>>>> This will calculate the rain difference between two records in weewx >>>>> sql based on the principle that the counter is reset to zero at midnight >>>>> -> >>>>> PERFECT FOR THE RAIN 24H ! >>>>> >>>>> Small additional question: if we wish to constantly calculate the >>>>> difference between two records values of a meter which *never* resets >>>>> to zero (such as an electricity or water meter), how should we proceed? >>>>> >>>>> THANKS >>>>> >>>>> Le jeudi 18 janvier 2024 à 14:05:10 UTC+1, Tom Keffer a écrit : >>>>> >>>>>> Unfortunately (for you), WeeWX mostly uses observation type "rain", >>>>>> the amount of rain that fell since the last loop packet (what you are >>>>>> calling "instantaneous rain"). >>>>>> >>>>>> You should assign the rain since midnight to type "dayRain". >>>>>> >>>>>> Then calculate "rain" as the difference between successive >>>>>> "dayRain" values. While this is a pretty simple calculation, there is an >>>>>> xtype that can do it for you. See class Delta in weewx.wxxtypes >>>>>> <https://github.com/weewx/weewx/blob/master/src/weewx/wxxtypes.py#L586>. >>>>>> To use it, add this to weewx.conf: >>>>>> >>>>>> [StdWXCalculate] >>>>>> [[Calculations]] >>>>>> ... >>>>>> [[Delta]] >>>>>> [[[rain]]] >>>>>> input = dayRain >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> On Wed, Jan 17, 2024 at 11:47 PM Remy Lavabre <remy.l...@gmail.com> >>>>>> wrote: >>>>>> >>>>>>> Good morning, >>>>>>> >>>>>>> I created a [driver] for weewx to retrieve data from the Awekas API >>>>>>> (my Bresser weather station does not have a USB port). >>>>>>> >>>>>>> This works but regarding the rain, it is not the instantaneous rain >>>>>>> (from a packetloop) that we recover but the rain over 24 hours since >>>>>>> midnight. >>>>>>> Is there a "simple" way to tell WeeWX that the packetsloop rain data >>>>>>> corresponds to the cumulative rain since midnight and not the rain that >>>>>>> fell during the data retrieval interval (the time gap between two >>>>>>> packetsloops) ? >>>>>>> >>>>>>> Thank you so much... >>>>>>> >>>>>>> -- >>>>>>> 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 weewx-user+...@googlegroups.com. >>>>>>> To view this discussion on the web visit >>>>>>> https://groups.google.com/d/msgid/weewx-user/9887101f-fcc1-45ce-948e-e03429bf7baan%40googlegroups.com >>>>>>> >>>>>>> <https://groups.google.com/d/msgid/weewx-user/9887101f-fcc1-45ce-948e-e03429bf7baan%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 weewx-user+...@googlegroups.com. >>>> >>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/weewx-user/796eb84f-ad09-41bf-ad90-202ad6f05773n%40googlegroups.com >>>> >>>> <https://groups.google.com/d/msgid/weewx-user/796eb84f-ad09-41bf-ad90-202ad6f05773n%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 weewx-user+...@googlegroups.com. >> > To view this discussion on the web visit >> https://groups.google.com/d/msgid/weewx-user/4b738c28-b1f5-43ee-a268-8782eaec19a9n%40googlegroups.com >> >> <https://groups.google.com/d/msgid/weewx-user/4b738c28-b1f5-43ee-a268-8782eaec19a9n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > -- You received this message because you are subscribed to the Google Groups "weewx-user" group. 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