Suggesting use of $hour_delta=1 wasn’t wise on my part as data arriving once per 60 minutes will likely lead to some occasions where no data is displayed depending on exactly when the data arrives. Conceivably data arriving or being processed a few seconds late could fall outside of $hour_delta=1.
Actually, thinking some more, you my be able to use the aggregate ‘last’ to get the last value in the aggregation period, so try $span($hour_delta=2).co2.last. I may be mistaken but I think the aggregates exclude the None values so this tag may give you the most recent non-None value in the last two hours. Refer to http://weewx.com/docs/customizing.htm#Tag_$span and http://weewx.com/docs/customizing.htm#aggregation_types. Failing that you may like to try $span($time_delta=3900).co2.avg or 4200 to display the average over the last 70 or 80 minutes. Be aware though that just as $hour_delta=1 missed some records going the other way to > 1 hour will likely see more than one record be included in some aggregates, probably not an issue but something to be aware of. Gary On Sunday, 5 December 2021 at 08:35:01 UTC+10 [email protected] wrote: > I've tried a few suggestions. The sensor output time can be changed to a > shorter period but, at this point, I prefer to keep it at 60 minutes since > the internal battery looks impossible to change easily. At 60 minutes it is > supposed to last a little over 3 years. > > I added the suggestion " $span($hour_delta=1).co2.avg" which seems to > bring in data more often but there are still some periods of "N/A." > > I added " expires_after = none" but for now that doesn't seem to do > anything. > > The suggestion of writing data to a scratch file may be the only way to go > if I can't configure it another way. > > I have produced a daily graph on the main page > > [image: yafe6kzk.bmp] > > The sensor is in the house for now and the peaks seem to come from using > the oven and burners on the gas stove. > > Thanks for all the help. I'll give this a day or so to accumulate some > data. > On Saturday, December 4, 2021 at 4:46:26 PM UTC-5 [email protected] wrote: > >> Bob, >> As noted earlier, now that you have a base MQTTSubscribe configuration up >> and running, you probably want to look at its 'archive record cache >> capability'. Details are here, >> >> https://github.com/bellrichm/WeeWX-MQTTSubscribe/wiki/Configuring-additional-options#expires_after >> >> I think that setting expires_after to none would be the simplest. So you >> would end up with something like this. >> [MQTTSubscribeService] >> [[topics]] >> [[[mytopic]]] >> ignore = true >> [[[[CO2_Value_PPM]]]] >> name = co2 >> ignore = false >> expires_after = none >> >> rich >> >> On Saturday, 4 December 2021 at 15:09:39 UTC-5 gjr80 wrote: >> >>> The other approach is to give WeeWX at least one co2 value per archive >>> period (it can be the same value) but that is a function of your data >>> source and the driver being used and I don’t know the >>> limitations/capabilities of each. >>> >>> Gary >>> >>> On Sunday, 5 December 2021 at 05:56:10 UTC+10 gjr80 wrote: >>> >>>> The issue here is that the ‘co2 field’ receives data only once per >>>> hour, so based on a 15 minute archive period only one in four archive >>>> records will have co2 data. Changing the accumulator type and extraction >>>> policy will not change this. I would leave the co2 accumulator settings >>>> out >>>> of weewx.conf. I doubt whether $last will be much help either; $last >>>> displays data from the last known good record in the database as opposed >>>> to >>>> the current record used by $current. If there is no co2 data in most >>>> records then $last will provide a similar result. >>>> >>>> You may have better luck with some sort of aggregate over the past >>>> hour, say something like (untested) $span($hour_delta=1).co2.avg. The >>>> actual aggregate is probably meaningless since you only have one value per >>>> hour so min be mx will work just as well. >>>> >>>> Gary >>>> On Sunday, 5 December 2021 at 03:59:46 UTC+10 [email protected] wrote: >>>> >>>>> Sorry, here is some info. This time, I re-inserted the [Accumulator] >>>>> paragraph at a different place in weewx.conf and it restarted without an >>>>> exit. The web data is still showing "$last.co2" >>>>> It ran for a while and then stopped. Debug file attached. Thanks >>>>> weewx.conf >>>>> >>>>> # Options for 'MQTTSubscribeService' >>>>> [Accumulator] >>>>> [[co2]] >>>>> accumulator = firstlast >>>>> extractor = last >>>>> >>>>> [MQTTSubscribeService] >>>>> # This section is for the MQTTSubscribe service. >>>>> >>>>> # Turn the service on and off. >>>>> # Default is: true >>>>> # Only used by the service. >>>>> enable = true # false >>>>> ================================================== >>>>> index.html.tmpl >>>>> <tr class = "even"> >>>>> <td class="stats_label">105 Crawl Temperature</td> >>>>> <td class="stats_data">$current.extraTemp1 / >>>>> $current.extraTemp1.degree_C</td> >>>>> </tr> >>>>> <tr class = "even"> >>>>> <td class="stats_label">CO2 level</td> >>>>> <td class="stats_data">$last.co2</td> >>>>> </tr> >>>>> >>>>> >>>>> ================================================== >>>>> >>>>> Standard web page reads: (http://grattans.org/wx) >>>>> >>>>> 105 Crawl Temperature 72.0°F / 22.2°C >>>>> CO2 level $last.co2 >>>>> >>>>> On Saturday, December 4, 2021 at 12:07:09 PM UTC-5 vince wrote: >>>>> >>>>>> On Saturday, December 4, 2021 at 7:16:00 AM UTC-8 [email protected] >>>>>> wrote: >>>>>> >>>>>>> I tried changing $current.co2 to $last.co2 but it only printed >>>>>>> "$last.co2" on the web page. >>>>>>> >>>>>>> Adding the [Accumulator] section to weewx.conf only caused an error >>>>>>> and exit when I restarted weewx. I tried adding this in several places >>>>>>> but >>>>>>> none seems to let weewx restart without an exit error. Is there a >>>>>>> special >>>>>>> place to add this? Couldn't find anything in the doc about placement. >>>>>>> Thanks >>>>>>> >>>>>>> >>>>>> Usual answers apply. >>>>>> >>>>>> Unless you post the error messages verbatim and/or the changes you >>>>>> made to the skin, we are not going to be able to help you. >>>>>> >>>>>> >>>>> -- 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/60583ac3-73f3-479c-91d0-34fcdf1c0865n%40googlegroups.com.
