[GRASS-user] r.mapcalc: compare two maps [RESOLVED]

[Laurent C.]

2017-03-30 12:38 GMT-06:00 Rich Shepard <rshepard at appl-ecosys.com>:
> On Thu, 30 Mar 2017, Laurent C. wrote:
>
>> You can create a new vector map and create a line that link the two
>> points. However, r.carve will interpolate the elevation between the start
>> point and the end point.
>
>
> Laurent,
>
>   Have this line in a vector map called 'stream.'
>
>> If you culvert invert have a lower elevation, this will not show up. But
>> considering the amount of simplification you're already applying, it could
>> be acceptable.
>
>
>   The invert has a slightly higher elevation than the outfall. Both are
> lower than the elevation of the road over the culvert.

Rich,

In that case, you will not see the accumulation upstream the culvert
that should normally occur if the pipe is actually higher than the
ground.
Please note that in a future version, Itzï will be able to model
culverts more accurately thanks to a coupled drainage model.
But this might be in a few months.

Regards,
Laurent