1592614500 1632611100 1632611400 1647688800 I can't see a pattern or any common features.
On Thursday, June 30, 2022 at 3:55:49 AM UTC-4 [email protected] wrote: > No, I never had weewx crashes related to the sunshine calculations. > > What are the dateTime values that trigger the error ? > > > > Le mercredi 29 juin 2022 à 23:23:16 UTC+2, Peter Fletcher a écrit : > >> Have you had any odd weewx errors or crashes related to the sunshine >> calculations? I ask because I hadn't, but I decided to try to 'backfill' my >> database with sunshine times, based on the 5-minute radiation values, and I >> ran into a bizarre bug. I used the code shown below (on a copy of my live >> weewx database). As you will see, the threshold calculation code is >> essentially identical to yours, except that it has been converted to a >> regular function (no 'self' parameter) and my station's latitude and >> longitude are hard coded in it. When the code is run under Python 3.9.2 on >> my Pi, it initially runs without problems, but crashes after 8,000+ records >> have been processed with a ValueError on the MaxThreshold vs threshold >> comparison, reporting that it can't compare a complex with a float! If I >> intercept and log the errors, it turns out that, for a few specific values >> of dateTime, the function returns a complex number! Even more bizarrely, it >> only seems to do that in the context of the running code. If I manually run >> through all the operations from the function code at the Python command >> line, using the value of dateTime that produces the first crash, all the >> intermediate results and the final result are sane floats. >> There appears to be a second issue, possibly related to my reading and >> writing the database at relatively high frequency, which stalls the process >> after about 18,000 records have been processed, but removing the database >> writes allows it to run to completion without abolishing the consistent, >> albeit infrequent, ValueErrors. >> >> [backfill.py] >> import sqlite3 >> from datetime import datetime >> import time >> from math import sin, cos, pi, asin >> >> def sunshineThreshold(mydatetime): >> coeff = 0.9 # change to calibrate with your sensor >> utcdate = datetime.utcfromtimestamp(mydatetime) >> dayofyear = int(time.strftime("%j", time.gmtime(mydatetime))) >> theta = 360 * dayofyear / 365 >> equatemps = 0.0172 + 0.4281 * cos((pi / 180) * theta) - 7.3515 * sin( >> (pi / 180) * theta) - 3.3495 * cos(2 * (pi / 180) * theta) - >> 9.3619 * sin( >> 2 * (pi / 180) * theta) >> >> latitude = 43.0346213 >> longitude = -78.689362 >> >> corrtemps = longitude * 4 >> declinaison = asin(0.006918 - 0.399912 * cos((pi / 180) * theta) + >> 0.070257 * sin( >> (pi / 180) * theta) - 0.006758 * cos(2 * (pi / 180) * theta) + >> 0.000908 * sin( >> 2 * (pi / 180) * theta)) * (180 / pi) >> minutesjour = utcdate.hour * 60 + utcdate.minute >> tempsolaire = (minutesjour + corrtemps + equatemps) / 60 >> angle_horaire = (tempsolaire - 12) * 15 >> hauteur_soleil = asin(sin((pi / 180) * latitude) * sin((pi / 180) * >> declinaison) + cos( >> (pi / 180) * latitude) * cos((pi / 180) * declinaison) * cos((pi >> / 180) * angle_horaire)) * (180 / pi) >> seuil = (0.73 + 0.06 * cos((pi / 180) * 360 * dayofyear / 365)) * >> 1080 * pow( >> (sin(pi / 180) * hauteur_soleil), 1.25) * coeff >> return seuil >> >> >> database = 'weewx.sdb' >> >> maxThreshold=0 >> count=0 >> conn=sqlite3.connect(database) >> cur=conn.execute("SELECT dateTime, Radiation from archive") >> for row in cur: >> count += 1 >> if (row[1] is not None) and (row[1] > 20): >> threshold = sunshineThreshold(row[0]) >> if threshold > maxThreshold: >> maxThreshold = threshold >> if row[1] > threshold: >> conn.execute("UPDATE archive set SunshineTime = 5 WHERE dateTime >> = " + str(row[0])) >> if count % 1000 == 0: >> print(count, 'Max Threshold', maxThreshold) >> conn.close >> [/backfill.py] >> >> On Friday, June 10, 2022 at 3:29:40 AM UTC-4 [email protected] wrote: >> >>> On my side, I have looked at the CPU utilization on my raspberry Pi 3B+. >>> I have the mqtt service service installed, so at each loop all data of the >>> packet are sent to the mqtt broker. >>> >>> With mqtt and when calculations of the sunshine threshold is done for >>> each loop packet, the total CPU utilization of python3 is about 0.75% >>> With mqtt and without calculation of sunshine threshold : 0.5% of total >>> CPU. >>> >>> So one can estimate that 0.25 % of total CPU is needed for the >>> calculation of the threshold value for each LOOP packet. >>> >>> >>> Le 9 juin 2022 à 22:26, 'Peter Fletcher' via weewx-user < >>> [email protected]> a écrit : >>> >>> After some experimentation, I found that the radiation value in the VP2 >>> LOOP packets does, indeed, normally change every 50-52 seconds, but, >>> perhaps about a fifth of the 'gaps' are a *multiple* of that time - >>> most often 100+ or 150+ seconds, but occasionally more than that (I saw one >>> 250+ second 'gap'). I saw this under conditions of variable sunshine and >>> clouds when it seemed unlikely that the actual radiation value would have >>> been precisely constant for that length of time, so I am not sure exactly >>> what is going on. In any event, I am revising the code I am using on the >>> basis of doing the threshold calculation when the radiation level changes, >>> but at least every minute, if it remains constant for more than the normal >>> 50-52 seconds.. >>> >>> On Sunday, June 5, 2022 at 12:33:47 PM UTC-4 [email protected] wrote: >>> >>>> I think it is also OK to do an average for every 30 seconds. It >>>> depends also on the weather station used. >>>> For instance, a Davis Vantage Pro 2 ISS transmits an updated solar >>>> radiation value every 50 to 60 seconds. So with this weather station, even >>>> a 1 minute average would not be very different since anyway the solar >>>> radiation values of the LOOP packet are the same for at least 50 seconds.! >>>> >>>> Le 5 juin 2022 à 18:02, 'Peter Fletcher' via weewx-user < >>>> [email protected]> a écrit : >>>> >>>> I chose to average the LOOP radiation readings and only to do the >>>> threshold calculation and make the sun/no sun determination every 30 >>>> seconds because I thought doing it on every LOOP might overload LOOP >>>> processing (I am running weewx on a Pi 3B, which is also doing a few other >>>> things which use the CPU). If this is an unnecessary concern, as it may >>>> very well be, your modified code is much cleaner than mine. >>>> >>>> On Saturday, June 4, 2022 at 12:41:08 PM UTC-4 [email protected] >>>> wrote: >>>> >>>>> It is a very good idea to calculate the sunshine duration for each >>>>> LOOP packet and sum these values to make the final archive sunshine >>>>> duration. I have modified my script accordingly : >>>>> https://github.com/Jterrettaz/sunduration. >>>>> The logic is the following : for each received LOOP packet, the >>>>> radiation is compared to a calculated threshold. If the radiation is >>>>> above >>>>> the threshold value, the sunshine time for the LOOP packet is equal to >>>>> the >>>>> time elapsed between the previous loop packet and this packet (most of >>>>> the >>>>> time 2 seconds with a Vantage Davis Pro). >>>>> The final archive sunshine duration is the sum of all the LOOP value >>>>> within the archive period. >>>>> Le vendredi 3 juin 2022 à 21:59:36 UTC+2, Peter Fletcher a écrit : >>>>> >>>>>> That makes some sense when you are getting data from an 'external' >>>>>> sensor, though there are (IMHO) simpler ways of doing it. weewx already >>>>>> has >>>>>> access to the LOOP radiation data from the VP2, so handling the >>>>>> processing >>>>>> and data storage within weewx makes more sense to me in this case. >>>>>> >>>>>> On Friday, June 3, 2022 at 3:24:23 PM UTC-4 vince wrote: >>>>>> >>>>>>> On Friday, June 3, 2022 at 11:17:00 AM UTC-7 Meteo Oberwallis wrote: >>>>>>> >>>>>>>> if the interval of Weewx and the data logger is set to 10 minutes, >>>>>>>> I would have liked to read the value of the solar sensor every minute >>>>>>>> and >>>>>>>> then write it into a separate .sdb database as possible sunshine. >>>>>>> >>>>>>> >>>>>>> Personally I'd use an external program called via cron and posting a >>>>>>> message to a MQTT topic. Have weewx subscribe to that topic to get the >>>>>>> data into your db. >>>>>>> >>>>>>> This is how I used to get my DS18b20 temperature sensor data into >>>>>>> weewx. >>>>>>> >>>>>>> >>>> -- >>>> You received this message because you are subscribed to a topic in the >>>> Google Groups "weewx-user" group. >>>> To unsubscribe from this topic, visit >>>> https://groups.google.com/d/topic/weewx-user/19ylVTRqbh4/unsubscribe. >>>> To unsubscribe from this group and all its topics, send an email to >>>> [email protected]. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/weewx-user/0e631671-0a74-4963-9f1c-e5f81bc7c366n%40googlegroups.com >>>> >>>> <https://groups.google.com/d/msgid/weewx-user/0e631671-0a74-4963-9f1c-e5f81bc7c366n%40googlegroups.com?utm_medium=email&utm_source=footer> >>>> . >>>> >>>> >>>> >>> -- >>> You received this message because you are subscribed to a topic in the >>> Google Groups "weewx-user" group. >>> To unsubscribe from this topic, visit >>> https://groups.google.com/d/topic/weewx-user/19ylVTRqbh4/unsubscribe. >>> To unsubscribe from this group and all its topics, send an email to >>> [email protected]. >>> >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/weewx-user/f0ecc86f-a615-4a24-a43f-ee0d3963b8adn%40googlegroups.com >>> >>> <https://groups.google.com/d/msgid/weewx-user/f0ecc86f-a615-4a24-a43f-ee0d3963b8adn%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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