A "None" reading, a.k.a. missing values won't affect the average of the known values. So, assume the wind is constantly blowing at 20mph and you miss half of the the values, the calculated average is still 20mph. No (0, zero) wind has no direction, because it is a vector with zero length, which will be stored "None/null" in memry/database, at least in the weewx database. There won't be a zero wind value with a direction, if not manipulated elsewhere.
Rory Gillies schrieb am Donnerstag, 16. Januar 2025 um 12:33:45 UTC+1: > Hi Michael, > > Thanks for that. The problem is that it can drop out for a few hours with > higher wind from SSW to WSW which skews the average windspeed. I use WXSim > for forecasting so it's better to have a least some wind rather than none > at the wrong direction. Both are wrong, but injecting a random value > roughly around the average wind speed from roughly the right direction is - > IMHO - better overall. The problem will go away when the contractor comes > to replace it with a sonic anemometer at the beginning of February. The > issue only occurs when the wind is above 20mph from around the SW. This is > the second Davis anemometer that's died on me, the first one lasted just > over a year was replaced under warranty but that doesn't cover the £300 to > get it up on the roof! This one was installed last March so not even a year > working. > > If I throw away the erroneous values will that keep the correct wind speed > average? Also, I use RTGD and it will stop after a while if it doesn't get > any wind packets, which means a manual restart of WeeWX to get it running > again. > > You can see the problem here: www.360shetland.co.uk/weather > > Cheers, > > Rory > > On Thursday, January 16, 2025 at 10:43:31 AM UTC [email protected] > wrote: > >> Rory, did you try my proposed correction? Throwing away wrong values is >> imho the better choice over replacing them with other wrong values >> >> [email protected] schrieb am Donnerstag, 16. Januar 2025 um 11:42:06 >> UTC+1: >> >>> this should be: >>> >>> windSpeed * 1.15 if winDir is not None else 20 >>> >>> That being said, it shouldn't because it' s just a randomly guessed >>> value. >>> >>> Graham Eddy schrieb am Donnerstag, 16. Januar 2025 um 11:41:43 UTC+1: >>> >>>> i mis-spoke. no assignment in ‘else’ e.g. >>>> >>>> windSpeed = 20 if windSpeed == 0 else windSpeed*1.15 >>>> >>>> note: in this case, if windSpeed is None, then None*1.15 throws an >>>> error (silently, without enough debug level) and no action is taken i.e. >>>> it >>>> remains None >>>> *⊣GE⊢* >>>> >>>> On 16 Jan 2025, at 9:33 pm, 'Rory Gillies' via weewx-user < >>>> [email protected]> wrote: >>>> >>>> windSpeed = 20 if windSpeed == 0 else windSpeed == windSpeed * 1.15 >>>> >>>> >>>> -- 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 visit https://groups.google.com/d/msgid/weewx-user/10693da0-6ee7-4c71-9048-3a6dabf6c9d7n%40googlegroups.com.
