[GRASS-dev] question about any July changes in hydrology functions

[Glynn Clements]

Michael Barton wrote:

> >> 1. Is there any speed advantage/disadvantage to using r.mfilter over
> >> r.neighbors? At the moment, because we are trying to get rid of occasional
> >> spikes, I don't think that a weighted mean will give better results than an
> >> unweighted mean. But the only way to get functions like a weighted mean is
> >> to use r.mfilter, so it would be good to know if there are any known
> >> performance hits or if it is faster.
> > 
> > r.mfilter currently works with integers. AFAICT, there's no
> > fundamental reason why it can't be upgraded to FP.
> 
> Then, as is it won't work for us. If it can be upgraded to integers we can
> try it.

I've added an FP version, r.mfilter.fp.

I didn't modify r.mfilter as it turns out that there is some behaviour
which is specific to integer maps, and to the zero-is-null behaviour
of 4.x. It wasn't practical to add support for FP and null values
without breaking compatibility.

-- 
Glynn Clements <glynn at gclements.plus.com>