0 Degree Data Spikes - Webtags/Realtime/Highcharts

[Smithee]

Afternoon all,

I have just set up highcharts and realtime.txt via webtags as i have a second sensor on a Davis VP - all is working well apart from some notable spikes in the data - just wondering if anyone has any ideas?

http://www.casa.ucl.ac.uk/cumulus/daygraph.htm

Its looking like the webtags sometimes does not get any data so it reports 0 (?)

Any thoughts would be great...

Andy

[steve]

If it doesn't get any new data (i.e. the Davis DLL returns an error), it doesn't update the value, so it would be the same as the previous reading. You could watch the extra sensors screen in Cumulus, just to confirm that the reading does change to zero occasionally and it's not just an issue processing the web tag.

[mcrossley]

Very odd, I was going to suggest that it was failing to read the tag file as it was updated, but the other values don't seem to be affected.

[steve]

As it's the last value in the file, could it be that the file isn't complete when it's read by the script? Would it then take the value as zero?

[Smithee]

It does not seem to be the data in the realtime.txt - as if the graphs are left running all is fine, only on refresh, thus pulling in realtimelog.txt are the spikes there.

The log is via a batch file -

:start
copy /b realtime.log+realtime.txt realtime.tmp
tail --quiet --lines=1440 realtime.tmp > realtime.log
copy realtime.log Z:\casa\cumulus\realtimelog.txt
choice /C N /T 60 /D N /M "Wait for timeout..."
goto start

Not sure what to make of it to be honest....

Andy

[steve]

Looking at your realtimelog.txt, it appears that you are occasionally appending the "real" realtime.txt rather than your constructed version.

[Smithee]

That must be it - i have realtime turned on - which i assume creates realtime.txt. I then have the custom webtags to create realtime.txt in the settings! I will rename the webtags version and update accordingly, that should fix it.

Much appreciated as ever Steve...

Andy