[GRASS-user] Elevation above a river

[Shane Carey]

Hey Johannes,

Thanks for your reply. How does r.grow work if let's say the height above
the river reaches 1m at 3meters away from the river. And in an other area
it reaches the 1meter height at 2meters away from the river. Is it able to
follow that line?

Thanks

On Domh 16 MFómh 2018 at 17:21, Johannes Radinger <
johannesradinger at gmail.com> wrote:

> To me this looks like a flooding-related question, i.e. to extract the
> shore lines of a river if it's water level is raised by 1m or 3m?
> Maybe (1) extract the raster cells of the elevation map that represents
> the river channel, (2) then apply r.grow and (3) then r.mapcalc to subtract
> the grown river channel from the original elevation map.
> /Johannes
>
> On Sun, Sep 16, 2018 at 5:16 PM Markus Neteler <neteler at osgeo.org> wrote:
>
>> Hi,
>>
>> Shane Carey <careyshan at gmail.com> schrieb am Fr., 14. Sep. 2018, 23:02:
>>
>>> Hi All,
>>>
>>> Does anyone know is it possible to calculate the elevation above a river
>>> channel (actual river network that was digitised as opposed to being
>>> extracted from a DTM) from a DTM and create a polygon from it.
>>>
>>> I need to calculate heights of 1m and 3m above a river channel on both
>>> sides of the channel and create a polygon from it.
>>>
>>
>> This isn't clear to me. Could you elaborate?
>>
>> Best
>> Markus
>>
>>
>> Thanks all.
>>>
>>> Le gach dea ghui,
>>> *Shane Carey*
>>> *GIS and Data Solutions Consultant*
>>> _______________________________________________
>>> grass-user mailing list
>>> grass-user at lists.osgeo.org
>>> https://lists.osgeo.org/mailman/listinfo/grass-user
>>
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> --
Le gach dea ghui,
*Shane Carey*
*GIS and Data Solutions Consultant*
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