[GRASS5] s. -> v.

Mon Oct 18 15:55:56 EDT 2004

On Mon, 18 Oct 2004, Michael Barton wrote:

> Markus,
> 
> I am remembering this discussion about finishing or not finishing the
> kieging package better now, including Helena's note. This perhaps brings up
> the chance to think strategically about the direction for GRASS development.
> While there are always bugs to fix and tweaks to make, IMHO GRASS 5.7 is an
> outstanding piece of spatial technology that goes well beyond most GIS
> packages on the market. So, in which direction should future development
> head. I think that the survey that will soon be posted will be helpful in
> determining this. But here are a couple thoughts.
> 
> 1) Improvement in the UI. Radim is working on merging GRASS with QGIS. This
> is potentially exciting, especially with new display tools for vectors. We
> also need to greatly simplify the installation procedure. An easy way to add
> in special purpose packages (plugins in QGIS) without having to compile
> could be a huge boost to development efforts.
> 
> 2) Building on the volumetric tools. The beginning in GRASS is more than is
> available in most other (any other?) GIS systems. The display tools need to
> be integrated with NVIZ and we need more analysis and volume development
> tools.
> 
> 3) Improving the already rich set of spatial analysis tools with more
> spatial analysis and geospatial statistics. There was a rich thread recently
> dealing with developing tools for archaeological and geolophysical research.
> Benjamin Ducke has started in this direction. A krieging package would be
> another. Improvements and additions to packages for ecological analysis
> (e.g., r.le) would also be desireable.

While I can agree with the first two (a bit unwillingly because I really 
value the "paper trail" left in the readline history file when working at 
the command line), I would argue that we should be cautious on 3). The 
main reason is that linking tools seems to me a better option, because as 
Glynn has (rightly) said, much of the GRASS codebase has not been used 
much (at least recently), which means we just don't know if analysts 
should use it. For me active analysis means having access to a scripting 
language in which methods can be prototyped, and provides much more 
immediate debugging than looking at the C or Tck/Tk code. 

As things are now, especially after Edzer Pebesma's porting of gstat to S
(both S-PLUS and R), and after the release of R 2.0.0 with lazy loading of
packages, launching an R session from a batch file is fast and can do most
of what a hard-coded module can do (at least in principle).

Demonstrating this was why in an earlier post this evening I included
verbatim the code for s.kcv in R - for analysis, scripted interpreted
languages are the way to go until they are too slow for practical use.
Putting a GUI front end on a shell script calling R with a script is a
potentially cheap way of using calculation functions that are in daily use
by many people, and thus subject to just the kind of eyeballing Glynn was
refering to.

I think that getting the R-GRASS bridge to 5.4 is feasible, but I'd like 
to invite others to join in for 5.7. Edzer, Barry Rowlingson and I will be 
working together in Lancaster 2-5 November on classes for spatial data in 
S/R, there is an online access point through http://www.r-project.org/Rgeo,
and contributions of ideas would be most welcome. The R-GRASS bridge now 
contains a local copy of libes/gis/* files from about 5.0.2 with 
modifications (raster and sites files). I hope to put that as is on 
sourcefourge, and migrate to a version that links against 5.4 libgis, 
before beginning a third version aimed at 5.7 and with the new class 
support to interface vectors. Note that R is also getting Terralib support 
- anybody else interested in Terralib?

Please accept that I do understand that linking to R is not an answer to 
everything, but it isn't a bad answer to getting more analytical 
functionality in a flexible way, which can be coded for speed later if 
need be.

Roger

> 
> There are perhaps other strategic directions that others could add. I'd love
> to see all the them, but realize that it will be necessary to prioritize.
> 
> Michael
> 
> 
> 
> 
> On 10/18/04 2:24 AM, "Markus Neteler" <neteler at itc.it> wrote:
> 
> > On Sun, Oct 17, 2004 at 08:25:22PM +0100, Paul Kelly wrote:
> >> Hello Michael
> >> 
> >> On Sun, 17 Oct 2004, Michael Barton wrote:
> >> 
> >> [...]
> >>> Since GRASS doesn't have a krieging interpolator,
> >> 
> >> s.surf.krig?
> >> http://freegis.org/cgi-bin/viewcvs.cgi/grass/src/sites/s.surf.krig/
> >> http://www.geog.uni-hannover.de/grass/gdp/html_grass5/html/s.surf.krig.html
> >> 
> >> Looks substantial enough but I wonder what the problem with it is. Is it
> >> just another module that was disabled and forgotten like s.kcv, m.in.ntf
> >> or is there a more serious problem?
> > 
> > Some clues here:
> >  http://grass.itc.it/pipermail/grass5/2000-September/011898.html
> >  http://grass.itc.it/pipermail/grass5/2000-September/011895.html
> > 
> > AFAIK the update/rewrite wasn't finished.
> > 
> >  Have a look also here:
> >  http://intevation.de/rt/webrt?serial_num=256
> >  "Helena wrote:
> >> #256 s.surf.krig - kriging is much better served by linking with geostats
> >> packages as you need lots of additional tools to make it really useful -
> >> GSTATS and R-stats would be much better for that. Unless somebody wants to
> >> undertake major geostatistics developments fully integrated with GRASS
> >> (inclding s.sv and other tools) I suggest retiring it and rather work on
> >> improvements and education for R-stats bridge and GSTATS link"
> > 
> > 
> > Markus
> > 
> > 
> > 
> 
> ____________________
> C. Michael Barton, Professor of Anthropology
> School of Human, Cultural, and Social Change
> PO Box 872402
> Arizona State University
> Tempe, AZ  85287-2402
> USA
> 
> Phone: 480-965-6262
> Fax: 480-965-7671
> www: <www.public.asu.edu/~cmbarton>
> 
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-- 
Roger Bivand
Economic Geography Section, Department of Economics, Norwegian School of
Economics and Business Administration, Breiviksveien 40, N-5045 Bergen,
Norway. voice: +47 55 95 93 55; fax +47 55 95 93 93
e-mail: Roger.Bivand at nhh.no