Your are correct that the driver uses 0.518 mm per bucket tip. However, somewhere in the code it gets rounded up to 0.52 mm per bucket tip. This would explain my 0.0204724409. Not sure where that happens exactly in the driver. I will have to look at the driver more to find out were that happens. Either way, the problem with rounding up the sum remains.
On Sunday, December 18, 2016 at 12:29:14 AM UTC-7, gjr80 wrote: > > I still think there is something screwy here. The lacrosse 23xx driver > uses 0.518mm per bucket tip. weewx uses 25.4mm per inch so that is > 0.0203937 inches per tip. So in your database you will see multiples of > this value in the rain field (assuming you are using US customary units in > your database). So if there were 2 tips in an archive period you should see > 0.0407874 which is significantly different to the 0.04051811 number you > have. That will certainly lead to discrepancies over a period of time. The > irony of it is consider the month that had 0.32 inches. There was 16 bucket > tips that month. if you take 16 bucket tips x 0.0203937 inches per tip you > get 0.32629921 inches which is correctly rounded to 0.33 inches. > 16 decimal places may be stored in the database but anything after 5 or 6 > places will have no affect on anything weewx displays unless you are > looking at a period that has 1000s of tips. > > Changing the formatting may give an acceptable result in this case but the > issue will reappear at sometime while the above discrepancy remains. > > Gary > > -- 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.
