The fact remains that the driver emits rain as 0.518mm or 0.020393701 inches per tip. Since it is a tipping rain gauge the database should only record multiples of this figure. Your initial email mentions 2 numbers; 0.040551181102 etc and 0.32519685039 etc. The first is clearly meant to be 2 tips and the second 16 tips. But using the tip value in the driver these numbers should be 0.040787402 and 0.326299216, about 0.6% and 0.1% under respectively. Not a huge amount but enough to cause the types of errors you have seen, particularly when the 3rd digit of the rain figure concerned is around about 5. Dealing with floats in python adds some inherent inaccuracy to the resulting values but this is typically only comes into play somewhere around the 10th or 11th decimal place, way to small to have an effect here. Sure you can make things look ok by changing the formatting or the calculations if you dare, but these are only cosmetic fixes that will mask the issue in this case but it will recur in other cases (what happens if you use 3 decimal places and then you get a 5 in the fourth decimal place?).
I don't believe there is any need to change the underlying weewx formatting/conversion machinery whilst the above anomalies remain. 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.
