[Tagging] units and notations for depth

[Warin]

On 19/02/19 14:03, Graeme Fitzpatrick wrote:
>
> On Tue, 19 Feb 2019 at 12:45, Warin <61sundowner at gmail.com 
> <mailto:61sundowner at gmail.com>> wrote:
>
>     The wiki has no units for depth, I would suggest these be the same as
>     height.
>
>
> Makes sense - default as m's, but can be marked as ft depending on 
> local standards
>
>     There are also problems with estimation and variability.
>
>     Some are using the tilde mark '~' to indicate 'approximately'.
>
>     Some are using '-' for between eg depth=0.5-0.7 for between 0.5
>     and 0.7.
>
>     Any opposition or better ideas???
>
>
> Not opposition, but for tidal areas, isn't this going to have the same 
> problems of whether you mark the "coastline" at the high- or low-tide 
> line?
>
> You'd probably need something along the lines of
> Average_low-tide=0.8
> Average_high-tide=1.9

The depth at the high tide mark would usually go from 0 to some negative 
number.  and average would be a negative number.

The depth at the low tide mark would usually go from 0 to some positive 
number. So it could be mapped depth=0-1

I would not map those. But it does raise the problem of using'-' for 
'between' if there is any negative number to be used.

Is using 'to' an acceptable method to represent 'between'?

This comes out of the river navigation problem when I looked at what 
people were doing for variable depths.
--------------
For tidal or seasonal etc I would only tag the expected range .. thus

Average_low-tide=0.8
Average_high-tide=1.9

would become

depth=0.8-1.9 (or 0.8to1.9)


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