[GRASS-dev] Need ideas for a masters thesis...

Hamish hamish_b at yahoo.com
Sat Nov 14 22:52:52 EST 2009

Thomas wrote:
> If you come from a hydraulics background… one very
> important need is the ability to generate channel
> cross-sections interactively for, say, HEC-RAS and then do
> flood inundation mapping from HEC-RAS from the modeling
> results — I would think this would be a huge
> contribution.

to get a good cross section you need to set it perpendicular to the river's
center line. Which means you need a good river centerline. Which means you
have to deal with the "river mile problem". 

raster tools are not always good here as the river can be very thin
compared to the overall length leading to untenable resolution settings
to get an good result. (r.cost + r.param.scale to pull out the cost
ridges or r.slope.aspect to pull out the maxima from the 1st derivative
of the cost works, but the resolution issue gets ya)

any thoughts? some sort of reverse v.buffer?

small islands within the river also cause havoc with many computational



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