Calculating rain delta

[bell...@gmail.com]

MQTTSubscribe has support for calculating the delta value of an observation from the total. I know WeeWX added this support and want to move people to use the built-in support (or at least have new users use it). I wasn’t able to find much information on it, so just looking to verify some information.

1. This was added in 4.9.2 (issue #491)
2. To use it, the following needs to be added to weewx.conf (with the correct ‘input name’).

       [StdWXCalculate]

             [[Delta]]

                [[[rain]]]

                    input = totalRain

Thanks. rich

[gjr80]

I'm guessing by 4.9.2 you really meant 4.2.0? Support for StdWXCalculate calculation of deltas was added in v4.2.0, but the necessary XType was not loaded by weewx.conf (under a default install). This was corrected in v4.3.0.

I agree there is not much information describing the use of deltas in StdWXCalculate, I was looking for some information myself for another issue recently and all I found was the comments in the Delta XType declaration. The comments agree with your understanding, though I must confess to not having actually used a delta as yet. I will look to include something on StdWXCalculate deltas somewhere in the documentation.

Gary

[bell...@gmail.com]

Gary,

Thanks. I did mean 4.2 (wind and 4.9 is on my mind). I passed the info along.

rich