Topic: Interesting temp readings on new Weatherlink.com

[sward6368]

Noticed this odd display of earlier this winter of the daily high and low over 6,000 degrees F, but we haven't had more days below zero.  Saw this when looking at some public stations on weatherlink.com again this week.  Seems the new weatherlink.com or the ios app cant properly manage daily high and low displays when a negative is involved.
I emailed Davis support and sent the screen shot they asked for (they asked 3 times and I sent 3 times) and sent the new example today

Hopefully easy for them to figure out.

[LABob]

Programming-wise, I can't think of how they could cause that error. My only guess is an inexperienced coder messed up a db query so that it was performing some arithmetic on the data rather than selecting the MAX or MIN of the data set.

[johnd]

Maybe the Weatherlink subforum could be renamed 'Weatherlink and weatherlink.com'? (Probably don't need yet another new subforum?) Might be a more obvious place for posts like this which are obviously software-related rather than Davis hardware and I can see the number of such posts increasing in the future as the user-base for weatherlink.com continues to grow.

[LABob]

I think I figured out the error. It's a problem of going from signed numbers to unsigned numbers somewhere in their code. I wonder if the database is configured incorrectly so that the column for temp is an unsigned integer. For reasons I won't go into here, a programmer might convert decimal temperatures into an integer for storage (e.g. 55.6 would be stored as 556). In your image, -23.0 would be stored as -230. The problem comes when a signed number is converted to unsigned. -230 would turn into 65306. That means the lows and highs you see in your picture are really -10.0°F for the high and -23.3°F for the low. If those are the correct high and low, I would let Davis know that they have a signed vs. unsigned number problem on the back end (not that their front line techs will know what that means).

Turns out those are the correct numbers at the time the first post was made:



Case closed.

[sward6368]

Maybe the Weatherlink subforum could be renamed 'Weatherlink and weatherlink.com'? Might be a more obvious place for posts like this which are obviously software-related rather than Davis hardware and I can see the number of such posts increasing in the future as the user-base for weatherlink.com continues to grow.

I hadn't scrolled down far enough in the forum listings to notice a seperate weatherlink software forum.  Will use that in the future and try to move this one there

[johnd]

I hadn't scrolled down far enough in the forum listings to notice a seperate weatherlink software forum.  Will use that in the future and try to move this one there

Don't worry - comment wasn't aimed at you  . Just thinking that with increased use of weatherlink.com, it may not be 100% obvious where the best place for such posts might be.