kriging inside borders
My exact commands are :
library(maptools)
shapefile=read.shape('my.shp')
x=Map2poly(shapefile)
and the length is :
length(mappolys)
[1] 615
But i'm not sure that it's the good polylist object i need because it's a polygon grid in fact.
Thank you for your help
Chlo?
-----Message d'origine-----
De?: Roger Bivand [mailto:Roger.Bivand at nhh.no]
Envoy??: jeudi 19 mai 2005 19:07
??: Chloe ARCHINARD
Cc?: r-sig-geo at stat.math.ethz.ch
Objet?: Re: [R-sig-Geo] kriging inside borders
On Thu, 19 May 2005, Chloe ARCHINARD wrote:
Hello, I'm using geoR package to compute kriging with the function
krige.conv() and I used maptools (read.shape () + Map2poly () ) and
splancs (borders) packages to include a object of class polylist for the
attribute borders.
But I've got this message of error when 'borders' is in krige.conv () :
krige.conv: there are no prediction locations inside the borders. My
polylist is not good? The coordinates seam to be OK when I draw a map
with this polylist object. And if I use 'borders' in the contour
function : message error is :
Error in as.data.frame.default(borders) : can't coerce class "polylist"
into a data.frame
Firstly, it does help if the exact commands are given, rather than your
choice of them. I think the main issue here is that a polylist object is a
list of matrices with attributes, not a matrix. If your polylist object
is:
x <- Map2poly(read.shape("my.shp"))
what is length(x)? If it is 1, you may be able to say x[[1]] to extract
the first matrix in the list, but even then it may not work. If you can
show us the commands you are giving, and the length of your polylist
object, it should be possible to find something that works.
If someone could help me, thanks a lot!
Chlo? Archinard
-- 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 -- passerelle antivirus du campus CNRS de Montpellier --
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