When you use a tag that specifies an aggregation period, like $day, then
you have to specify an aggregation type, like max. See the Customizing
Guide, section *Aggregation periods
<http://weewx.com/docs/customizing.htm#general_aggregation_periods>*. So,
if you say $day.windrun, you're using an incomplete tag, one which has no
conversion operator to a string. Only the complete tags, such as
$day.windrun.max, has this.

Incidentally, this shows the hazards of defining windrun as the total
windrun since midnight. This makes it a monotonically increasing series,
starting each day at midnight.  A tag like $day.windrun.max is not as
useful as it could be, as it will always just be the last value in this
series. I wish it was treated more like rain, where the windrun is just the
run over the archive period. You'd have to do the sum to get the total run
since midnight ($day.windrun.sum), but then a tag like $day.windrun.max
would be more meaningful and useful.

But, that was an algorithmic mistake made a while ago. I think it would be
tough to redefine it now. Matthew, I'd be interested in your opinion.

-tk

On Sun, Dec 31, 2017 at 1:34 PM, Michael Hornsby <
[email protected]> wrote:

>
>
> Hi
>
> Can I get some advice on how to extract the windrun data for display ?
>
> This gives me spaces
> $day.windrun
> $week.windrun
> $month.windrun
> $year.windrun
>
>
> This gives me the same number for day and week (below)
> $day.windrun.max
> $week.windrun.max
> $month.windrun.max
> $year.windrun.max
>
> Day: 54.1 km
> Week: 54.1 km
> Month: 684.8 km
> Year: 829.6 km
>
> Cheers
> Michael
>
> --
> 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.
>

-- 
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.

Reply via email to