[STATSGRASS] Any suggestions?

[Roger Bivand]

On Tue, 17 Oct 2006, Raffaele Morelli wrote:

> > > So I can read and plot those attributes without running R inside a GRASS
> > > session.
> > > Did I understand?
> >
> > Yes, exactly. The geometries are stored in GRASS, is that correct?
> 
> 
> Yes.
> Should I store geometries too in MySQL for best performances?

I think that the slowness of the interface would remove any saving there - 
leaving the geometries in GRASS is, I think, fine.

> 
> For errors in R of any kind, please include the output of:
> >
> > traceback()
> >
> > issued immediately after the error.
> 
> 
> I was too hurry, now everything it's ok, the error disappeared using
> remove.duplicates=TRUE when launching readVECT6, cause some areas "share"
> the same category in my vector.
> 

Aha! I've been bitten by that too - it does need care, and it isn't 
obvious how to automate it so that multiple polygons belong to the same 
attribute table record (data frame row in R).

Please do check that the data in the database and in R are the same (for a 
small subset) when using remove.duplicates=TRUE - they should be, but it 
doesn't do any harm to check.

Roger


> I will follow your precious suggestions and send you feedbacks about
> visualization and data handling.
> 
> Again.
> Cheers
> 

-- 
Roger Bivand
Economic Geography Section, Department of Economics, Norwegian School of
Economics and Business Administration, Helleveien 30, N-5045 Bergen,
Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43
e-mail: Roger.Bivand at nhh.no