[R-sig-Geo] Convert grids with 0/1 attribute to polygons with neighbor grids of same values merged
Roger Bivand
Roger.Bivand at nhh.no
Fri Jan 29 15:13:10 CET 2010
On Thu, 28 Jan 2010, zhijie zhang wrote:
>
> Sorry. It seems that the above idea is not easy to get through. I tried it
> for some time.
> Hope Someone else can solve it.
Almost there - you needed:
spol1 <- unionSpatialPolygons(as(spol, "SpatialPolygons"),
as.character(spol$xvs))
image(grd, axes=TRUE)
plot(spol1, add=TRUE)
to complete, then I guess promotion back to a SpatialPolygonsDataFrame,
then writing out for each type separately to shapefile.
Roger
>
> On Wed, Jan 27, 2010 at 10:13 PM, zhijie zhang <epistat at gmail.com> wrote:
>
>> Hi,
>> I cannot successfully do it, but may provide my idea on this. Somebody
>> else may solve it.
>> ###Example Data###
>> library(maptools)
>> gt <- GridTopology(c(0.05,0.05), c(0.1,0.1), c(10,10))
>> xv<-rnorm(length(coordinates(gt)[,1]))
>> xvs<-ifelse(xv>0.2,1,0)
>> grd <- SpatialGridDataFrame(gt,
>> data.frame(xvs),proj4string=CRS(as.character(NA)))
>> #grdM<-as.matrix(data.frame(coordinates(grd),grd at data))
>> #grdM[1:5,]
>> spplot(grd)
>> ####Transform into polygons####
>> spix <- as(grd, "SpatialPixelsDataFrame")
>> spol <- as(spix, "SpatialPolygonsDataFrame")
>> ####Create two subset polygons based on 0 or 1######
>> spol1<-spol[spol$xvs==1,]
>> plot(spol1) #Four polygons
>> spol0<-spol[spol$xvs==0,]
>> plot(spol0) #one separate grid and a large irregualr polygon
>> #From their plots,we can see they can merge into four polygons for "spol1"
>> and two polygons for "spol0".
>> ###If we plot their neighbors, it will be more clear to see how many
>> polygons there should be after merging ######
>> library(spdep)
>> nbs<-poly2nb(spol1, queen=TRUE)
>> plot(spol1) #Four polygons
>> plot.nb(nbs, coordinates(spol1),add=TRUE)
>>
>> nbs2<-poly2nb(spol0, queen=TRUE)
>> plot(spol0) #Two polygons
>> plot.nb(nbs2, coordinates(spol0),add=TRUE)
>> ###############
>> I wonder whether it is feasible for the following idea based on the queen
>> neighbors.
>> Step1:We can first select one grid, and merge it with its queen neighbors.
>> Then generate a new polygon for this merged grids.
>> Step2: Continue to merge the newly generated polygon with its queen
>> neighbors. Then generate a newer polygon for these merged grids.
>> Repeat step1 and step2 until all the related grids were merged. This is
>> one separate large polygon.
>> Step3: Then select another isolated grid, and repeat the step1 and step2
>> to generate another polygon.
>> Continue....Until all the separated polygons were merged.That is the
>> queen neighbors will be zero finally.
>> Is this possible? Hope someone can solve this.
>> Some other ideas maybe better.
>>
>>
>>
>> On Wed, Jan 27, 2010 at 6:00 AM, <r-sig-geo-request at stat.math.ethz.ch>wrote:
>>
>>> Send R-sig-Geo mailing list submissions to
>>> r-sig-geo at stat.math.ethz.ch
>>>
>>> To subscribe or unsubscribe via the World Wide Web, visit
>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>>> or, via email, send a message with subject or body 'help' to
>>> r-sig-geo-request at stat.math.ethz.ch
>>>
>>> You can reach the person managing the list at
>>> r-sig-geo-owner at stat.math.ethz.ch
>>>
>>> When replying, please edit your Subject line so it is more specific
>>> than "Re: Contents of R-sig-Geo digest..."
>>>
>>>
>>> Today's Topics:
>>>
>>> 1. Re: rgdal 64bit Windows version? (Rainer Hurling)
>>> 2. Re: points to lines and/or polygons (Roger Bivand)
>>> 3. Distance to (nearest) polygon (Karl Ove Hufthammer)
>>> 4. Re: Distance to (nearest) polygon (Roger Bivand)
>>> 5. maxdist for kriging with an external drift (Els Verfaillie)
>>> 6. Re: maxdist for kriging with an external drift (Edzer Pebesma)
>>> 7. Re: maxdist for kriging with an external drift
>>> (Cutberto Uriel Paredes Hern?ndez)
>>> 8. Edit a Sptial Lines Object (Rodrigo Aluizio)
>>> 9. Re: maxdist for kriging with an external drift (Edzer Pebesma)
>>> 10. Re: maxdist for kriging with an external drift
>>> (Paulo Justiniano Ribeiro Jr)
>>> 11. Convert grids with 0/1 attribute to polygons with neighbor
>>> grids of same values merged (rusers.sh)
>>> 12. Re: complement part of a polygon in another polygon (rusers.sh)
>>> 13. kriging as fish swim, not as crows fly (Martin Renner)
>>> 14. Re: Distance to (nearest) polygon (Karl Ove Hufthammer)
>>> 15. Re: kriging as fish swim, not as crows fly (Michael Sumner)
>>>
>>>
>>> ----------------------------------------------------------------------
>>>
>>> Message: 1
>>> Date: Tue, 26 Jan 2010 12:01:45 +0100
>>> From: Rainer Hurling <rhurlin at gwdg.de>
>>> To: Michael Sumner <mdsumner at gmail.com>
>>> Cc: r-sig-geo at stat.math.ethz.ch
>>> Subject: Re: [R-sig-Geo] rgdal 64bit Windows version?
>>> Message-ID: <4B5ECB99.4040602 at gwdg.de>
>>> Content-Type: text/plain; charset=UTF-8; format=flowed
>>>
>>> Am 25.01.2010 22:25 (UTC+1) schrieb Michael Sumner:
>>>> I suspect you'll need to build GDAL for yourself and then build rgdal
>>>> on top of that, since rgdal depends upon a pre-installation of GDAL.
>>>> The gdal-dev list is the appropriate place for discussing the first
>>>> step.
>>>>
>>>> Colleagues have succesfully built 64-bit Windows GDAL from the 1.6.0
>>>> release using extra binaries (HDF4/5, NetCDF, etc.) from here:
>>>> http://vbkto.dyndns.org:1280/sdk/Default.aspx
>>>
>>> Thanks, Michael, for this interesting link.
>>>
>>> Unfortunately we are not able to build our own versions on windows
>>> machines because of administrative reasons. I will have a look at it in
>>> my spare time ;-)
>>>
>>> Rainer
>>>
>>>> There are notes on build rgdal for Windows here, but I've not done it
>>>> myself for a while:
>>>>
>>>> file.show(system.file("README.windows", package="rgdal"))
>>>>
>>>> I am keen to try this for myself, but it will not be for a while yet.
>>>>
>>>> Best regards,
>>>> Mike
>>>>
>>>> On Tue, Jan 26, 2010 at 8:04 AM, Rainer Hurling<rhurlin at gwdg.de>
>>> wrote:
>>>>> Some days ago Brian Ripley and Uwe Ligges announced an update to
>>> MinGW-w64
>>>>> builds for 64-bit Windows on R-devel at . This daily version works really
>>> nice.
>>>>> But it is not fully applicable at this time because of some missing
>>>>> packages.
>>>>>
>>>>> I am in particular interested in a 64-bit version of rgdal, which
>>> depends on
>>>>> a 64-bit version of gdal(.dll). Is their anything known about what is
>>>>> planned with this important part of spatial software?
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 2
>>> Date: Tue, 26 Jan 2010 13:54:27 +0100 (CET)
>>> From: Roger Bivand <Roger.Bivand at nhh.no>
>>> To: Agustin Lobo <alobolistas at gmail.com>
>>> Cc: r-sig-geo at stat.math.ethz.ch
>>> Subject: Re: [R-sig-Geo] points to lines and/or polygons
>>> Message-ID: <alpine.LRH.2.00.1001261350580.14929 at reclus.nhh.no>
>>> Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed
>>>
>>> On Tue, 26 Jan 2010, Agustin Lobo wrote:
>>>
>>>> Hi!
>>>> Package StatDA
>>>> provides background geoinformation as a set of coordinates:
>>>>> str(kola.background)
>>>> List of 4
>>>> $ boundary:'data.frame': 50 obs. of 2 variables:
>>>> ..$ V1: num [1:50] 388650 388160 386587 384035 383029 ...
>>>> ..$ V2: num [1:50] 7892400 7881248 7847303 7790797 7769214 ...
>>>> $ coast :'data.frame': 6259 obs. of 2 variables:
>>>> ..$ V1: num [1:6259] 438431 439102 439102 439643 439643 ...
>>>> ..$ V2: num [1:6259] 7895619 7896495 7896495 7895800 7895542 ...
>>>> $ borders :'data.frame': 504 obs. of 2 variables:
>>>> ..$ V1: num [1:504] 417575 417704 418890 420308 422731 ...
>>>> ..$ V2: num [1:504] 7612984 7612984 7613293 7614530 7615972 ...
>>>> $ lakes :'data.frame': 6003 obs. of 2 variables:
>>>> ..$ V1: num [1:6003] 547972 546915 NA 547972 547172 ...
>>>> ..$ V2: num [1:6003] 7815109 7815599 NA 7815109 7813873 ...
>>>>
>>>> is there any spatial function aready availale to convert these
>>> coordinates
>>>> into Spatial Lines and Spatial Polygons?
>>>
>>> This seems to work at least for SpatialLines - for polygons, the rings may
>>> need to be closed:
>>>
>>> library(StatDA)
>>> data(kola.background)
>>> xy <- kola.background$boundary
>>> names(xy) <- c("x", "y")
>>> library(maptools)
>>> bdy <- map2SpatialLines(xy)
>>> plot(bdy)
>>>
>>> The data are in the legacy S format (like the maps package).
>>>
>>> Roger
>>>
>>>
>>>>
>>>> Thanks
>>>>
>>>> Agus
>>>>
>>>> [[alternative HTML version deleted]]
>>>>
>>>> _______________________________________________
>>>> R-sig-Geo mailing list
>>>> R-sig-Geo at stat.math.ethz.ch
>>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>>>>
>>>
>>> --
>>> 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
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 3
>>> Date: Tue, 26 Jan 2010 16:02:27 +0100
>>> From: Karl Ove Hufthammer <karl at huftis.org>
>>> To: r-sig-geo at stat.math.ethz.ch
>>> Subject: [R-sig-Geo] Distance to (nearest) polygon
>>> Message-ID: <MPG.25c9226ee5625bb49896d3 at news.gmane.org>
>>> Content-Type: text/plain; charset="us-ascii"
>>>
>>> Dear list members
>>>
>>> Is there an easy and preferably fast way to measure the distance from a
>>> of (large) number of points to the nearest polygon? spDistsN1 seems to
>>> only want to measure the distance between points.
>>>
>>> For example, I need the distance between points at sea to the nearest
>>> land area (as defined by for example the 'world' dataset).
>>>
>>> It's not very important which polygon, e.g., country, the given distance
>>> is to. It would be nice if the 'distance' from points that are inside
>>> the polygons were zero or negative, but it's not required -- distance to
>>> the polygon border, e.g., shoreline, would be OK.
>>>
>>> --
>>> Karl Ove Hufthammer
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 4
>>> Date: Tue, 26 Jan 2010 16:27:23 +0100 (CET)
>>> From: Roger Bivand <Roger.Bivand at nhh.no>
>>> To: Karl Ove Hufthammer <karl at huftis.org>
>>> Cc: r-sig-geo at stat.math.ethz.ch
>>> Subject: Re: [R-sig-Geo] Distance to (nearest) polygon
>>> Message-ID: <alpine.LRH.2.00.1001261625260.17754 at reclus.nhh.no>
>>> Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed
>>>
>>> On Tue, 26 Jan 2010, Karl Ove Hufthammer wrote:
>>>
>>>> Dear list members
>>>>
>>>> Is there an easy and preferably fast way to measure the distance from a
>>>> of (large) number of points to the nearest polygon? spDistsN1 seems to
>>>> only want to measure the distance between points.
>>>>
>>>> For example, I need the distance between points at sea to the nearest
>>>> land area (as defined by for example the 'world' dataset).
>>>>
>>>> It's not very important which polygon, e.g., country, the given distance
>>>> is to. It would be nice if the 'distance' from points that are inside
>>>> the polygons were zero or negative, but it's not required -- distance to
>>>> the polygon border, e.g., shoreline, would be OK.
>>>
>>> There are methods for point to line segment distances in spatstat.
>>> Further, for projected (planar) coordinates, this could be added to
>>> R-Forge rgeos; for geographical coordinates Boost ggl would be needed.
>>>
>>> Roger
>>>
>>>>
>>>>
>>>
>>> --
>>> 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
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 5
>>> Date: Tue, 26 Jan 2010 17:00:29 +0100
>>> From: "Els Verfaillie" <els.verfaillie at ugent.be>
>>> To: <r-sig-geo at stat.math.ethz.ch>
>>> Subject: [R-sig-Geo] maxdist for kriging with an external drift
>>> Message-ID: <005d01ca9ea0$aed17900$0c746b00$@verfaillie at ugent.be>
>>> Content-Type: text/plain
>>>
>>> Dear list,
>>>
>>>
>>>
>>> I want to use Kriging with an external drift for a sedimentological
>>> dataset
>>> of grain-size that has a linear relation with the depth.
>>>
>>> Am I correct that when I set a 'maxdist' using the krige command, that a
>>> trend for the primary variable (grain-size) is calculated as a local
>>> linear
>>> function of the secondary variable (depth)? Is this function thus
>>> different
>>> for each interpolation window?
>>>
>>>
>>>
>>> d50.ked.dir50 <- krige(D50F~depth, locations=ds50, newdata=Depth,
>>> model=d50.fit.var.50, nmin=2, nmax=16, maxdist=9000)
>>>
>>>
>>>
>>> Thank you for your help.
>>>
>>>
>>>
>>> Best regards,
>>>
>>> Els Verfaillie
>>>
>>>
>>>
>>> ______________________________________________
>>>
>>> Dr. Els Verfaillie
>>>
>>> Carto-GIS cluster
>>>
>>> Ghent University (UGent) - Department of Geography
>>>
>>> ______________________________________________
>>>
>>>
>>>
>>>
>>>
>>>
>>> [[alternative HTML version deleted]]
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 6
>>> Date: Tue, 26 Jan 2010 17:05:03 +0100
>>> From: Edzer Pebesma <edzer.pebesma at uni-muenster.de>
>>> To: Els Verfaillie <els.verfaillie at ugent.be>
>>> Cc: r-sig-geo at stat.math.ethz.ch
>>> Subject: Re: [R-sig-Geo] maxdist for kriging with an external drift
>>> Message-ID: <4B5F12AF.5070302 at uni-muenster.de>
>>> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>>>
>>> Yes, that is right.
>>>
>>> Els Verfaillie wrote:
>>>> Dear list,
>>>>
>>>>
>>>>
>>>> I want to use Kriging with an external drift for a sedimentological
>>> dataset
>>>> of grain-size that has a linear relation with the depth.
>>>>
>>>> Am I correct that when I set a 'maxdist' using the krige command, that a
>>>> trend for the primary variable (grain-size) is calculated as a local
>>> linear
>>>> function of the secondary variable (depth)? Is this function thus
>>> different
>>>> for each interpolation window?
>>>>
>>>>
>>>>
>>>> d50.ked.dir50 <- krige(D50F~depth, locations=ds50, newdata=Depth,
>>>> model=d50.fit.var.50, nmin=2, nmax=16, maxdist=9000)
>>>>
>>>>
>>>>
>>>> Thank you for your help.
>>>>
>>>>
>>>>
>>>> Best regards,
>>>>
>>>> Els Verfaillie
>>>>
>>>>
>>>>
>>>> ______________________________________________
>>>>
>>>> Dr. Els Verfaillie
>>>>
>>>> Carto-GIS cluster
>>>>
>>>> Ghent University (UGent) - Department of Geography
>>>>
>>>> ______________________________________________
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> [[alternative HTML version deleted]]
>>>>
>>>> _______________________________________________
>>>> R-sig-Geo mailing list
>>>> R-sig-Geo at stat.math.ethz.ch
>>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>>>>
>>>
>>> --
>>> Edzer Pebesma
>>> Institute for Geoinformatics (ifgi), University of M?nster
>>> Weseler Stra?e 253, 48151 M?nster, Germany. Phone: +49 251
>>> 8333081, Fax: +49 251 8339763 http://ifgi.uni-muenster.de
>>> http://www.52north.org/geostatistics e.pebesma at wwu.de
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 7
>>> Date: Tue, 26 Jan 2010 16:45:00 +0000
>>> From: Cutberto Uriel Paredes Hern?ndez <cutberto.paredes at gmail.com>
>>> To: Edzer Pebesma <edzer.pebesma at uni-muenster.de>,
>>> r-sig-geo at stat.math.ethz.ch
>>> Subject: Re: [R-sig-Geo] maxdist for kriging with an external drift
>>> Message-ID:
>>> <8f1fabf91001260845n632ad13ek418a695e27110de8 at mail.gmail.com>
>>> Content-Type: text/plain; charset=ISO-8859-1
>>>
>>> Dear Edzer,
>>>
>>> Would it be correct to say then that if a neighbourhood is specified
>>> in the krige command the result would be that of Kriging with an
>>> External Drift (KED), otherwise it would be that of Simple Kriging
>>> with varying local means (SKlm)?
>>>
>>> Apologies for posting on this thread but I was about to post a
>>> similiar question.
>>>
>>> Thanks, Cutberto.
>>>
>>> 2010/1/26 Edzer Pebesma <edzer.pebesma at uni-muenster.de>:
>>>> Yes, that is right.
>>>>
>>>> Els Verfaillie wrote:
>>>>>
>>>>> Dear list,
>>>>>
>>>>>
>>>>> I want to use Kriging with an external drift for a sedimentological
>>>>> dataset
>>>>> of grain-size that has a linear relation with the depth.
>>>>> Am I correct that when I set a 'maxdist' using the krige command, that
>>> a
>>>>> trend for the primary variable (grain-size) is calculated as a local
>>>>> linear
>>>>> function of the secondary variable (depth)? Is this function thus
>>>>> different
>>>>> for each interpolation window?
>>>>>
>>>>> d50.ked.dir50 <- krige(D50F~depth, locations=ds50, newdata=Depth,
>>>>> model=d50.fit.var.50, nmin=2, nmax=16, maxdist=9000)
>>>>>
>>>>>
>>>>> Thank you for your help.
>>>>>
>>>>>
>>>>> Best regards,
>>>>>
>>>>> Els Verfaillie
>>>>>
>>>>>
>>>>> ______________________________________________
>>>>>
>>>>> Dr. Els Verfaillie
>>>>>
>>>>> Carto-GIS cluster
>>>>>
>>>>> Ghent University (UGent) - Department of Geography
>>>>>
>>>>> ______________________________________________
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> ? ? ? ?[[alternative HTML version deleted]]
>>>>>
>>>>> _______________________________________________
>>>>> R-sig-Geo mailing list
>>>>> R-sig-Geo at stat.math.ethz.ch
>>>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>>>>>
>>>>
>>>> --
>>>> Edzer Pebesma
>>>> Institute for Geoinformatics (ifgi), University of M?nster Weseler
>>> Stra?e
>>>> 253, 48151 M?nster, Germany. Phone: +49 251 8333081, Fax: +49 251
>>> 8339763
>>>> ?http://ifgi.uni-muenster.de http://www.52north.org/geostatistics
>>>> ?e.pebesma at wwu.de
>>>>
>>>> _______________________________________________
>>>> R-sig-Geo mailing list
>>>> R-sig-Geo at stat.math.ethz.ch
>>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>>>>
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 8
>>> Date: Tue, 26 Jan 2010 15:02:40 -0200
>>> From: "Rodrigo Aluizio" <r.aluizio at gmail.com>
>>> To: "R Help" <r-sig-geo at stat.math.ethz.ch>
>>> Subject: [R-sig-Geo] Edit a Sptial Lines Object
>>> Message-ID: <4b5f2052.9c15f10a.7b9d.0861 at mx.google.com>
>>> Content-Type: text/plain; charset="iso-8859-1"
>>>
>>> Hi list, I?m trying to insert some coordinates at the end of an object
>>> (attached) component (BP[1]).
>>>
>>> But I?m not able to do so. I can?t isolate the coordinates, if I use the
>>> ?@lines? it turns into a list, but I need to keep the SpatialLines and S4
>>> structure, then I will be able to transform the closed lines into
>>> polygons.
>>>
>>> So, How can I insert the coordinates that will close the BP[1] line into
>>> this object without changing the object properties. Any Ideas?
>>>
>>> Thank you in advance.
>>>
>>>
>>>
>>> -------------------------------------------------------------
>>>
>>> MSc. <mailto:r.aluizio at gmail.com> Rodrigo Aluizio
>>>
>>> Centro de Estudos do Mar/UFPR
>>> Laborat?rio de Micropaleontologia
>>> Avenida Beira Mar s/n - CEP 83255-000
>>> Pontal do Paran? - PR - Brasil
>>> Fone: (41) 3511-8657
>>>
>>> Fax: (41) 3455-3623
>>>
>>>
>>>
>>> -------------- next part --------------
>>> An HTML attachment was scrubbed...
>>> URL: <
>>> https://stat.ethz.ch/pipermail/r-sig-geo/attachments/20100126/63ec934e/attachment-0001.html
>>>>
>>> -------------- next part --------------
>>> A non-text attachment was scrubbed...
>>> Name: BP.Rdata
>>> Type: application/octet-stream
>>> Size: 39731 bytes
>>> Desc: not available
>>> URL: <
>>> https://stat.ethz.ch/pipermail/r-sig-geo/attachments/20100126/63ec934e/attachment-0001.obj
>>>>
>>>
>>> ------------------------------
>>>
>>> Message: 9
>>> Date: Tue, 26 Jan 2010 21:11:47 +0100
>>> From: Edzer Pebesma <edzer.pebesma at uni-muenster.de>
>>> To: Cutberto Uriel Paredes Hern?ndez <cutberto.paredes at gmail.com>
>>> Cc: r-sig-geo at stat.math.ethz.ch
>>> Subject: Re: [R-sig-Geo] maxdist for kriging with an external drift
>>> Message-ID: <4B5F4C83.7040808 at uni-muenster.de>
>>> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>>>
>>> Oh, geostatistics and its funny naming conventions!
>>>
>>> I see local models vs. global models as a completely different modelling
>>> aspect (model decision, basically) then the SK/OK/UK differences. When
>>> building on the same tradition / body of literature you quote: in that
>>> case KED would be a special form of UK, having only a single
>>> non-coordinate predictor called 'external drift'.
>>>
>>> In my eyes (and that of the literature with more mathematical
>>> statistical grounding, such as Cressie 1993 and others), the difference
>>> between SK on the one hand and OK/UK on the other is that SK assumes
>>> that you know the mean or mean structure. SKlm is then residual kriging
>>> added to a known mean function.
>>>
>>> In the gstat R package you obtain SK by specifying a beta value (for the
>>> mean); SKlm by specifying one or more predictors and passing the (known)
>>> regression coefficients as beta; you obtain OK/UK by not specifying
>>> beta; a formula ending on ~1 results in OK with an unknown mean only.
>>>
>>> Ah, and then SK = simple kriging, OK = ordinary kriging, UK = universal
>>> kriging.
>>> --
>>> Edzer
>>>
>>> Cutberto Uriel Paredes Hern?ndez wrote:
>>>> Dear Edzer,
>>>>
>>>> Would it be correct to say then that if a neighbourhood is specified
>>>> in the krige command the result would be that of Kriging with an
>>>> External Drift (KED), otherwise it would be that of Simple Kriging
>>>> with varying local means (SKlm)?
>>>>
>>>> Apologies for posting on this thread but I was about to post a
>>>> similiar question.
>>>>
>>>> Thanks, Cutberto.
>>>>
>>>> 2010/1/26 Edzer Pebesma <edzer.pebesma at uni-muenster.de>:
>>>>
>>>>> Yes, that is right.
>>>>>
>>>>> Els Verfaillie wrote:
>>>>>
>>>>>> Dear list,
>>>>>>
>>>>>>
>>>>>> I want to use Kriging with an external drift for a sedimentological
>>>>>> dataset
>>>>>> of grain-size that has a linear relation with the depth.
>>>>>> Am I correct that when I set a 'maxdist' using the krige command, that
>>> a
>>>>>> trend for the primary variable (grain-size) is calculated as a local
>>>>>> linear
>>>>>> function of the secondary variable (depth)? Is this function thus
>>>>>> different
>>>>>> for each interpolation window?
>>>>>>
>>>>>> d50.ked.dir50 <- krige(D50F~depth, locations=ds50, newdata=Depth,
>>>>>> model=d50.fit.var.50, nmin=2, nmax=16, maxdist=9000)
>>>>>>
>>>>>>
>>>>>> Thank you for your help.
>>>>>>
>>>>>>
>>>>>> Best regards,
>>>>>>
>>>>>> Els Verfaillie
>>>>>>
>>>>>>
>>>>>> ______________________________________________
>>>>>>
>>>>>> Dr. Els Verfaillie
>>>>>>
>>>>>> Carto-GIS cluster
>>>>>>
>>>>>> Ghent University (UGent) - Department of Geography
>>>>>>
>>>>>> ______________________________________________
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> [[alternative HTML version deleted]]
>>>>>>
>>>>>> _______________________________________________
>>>>>> R-sig-Geo mailing list
>>>>>> R-sig-Geo at stat.math.ethz.ch
>>>>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>>>>>>
>>>>>>
>>>>> --
>>>>> Edzer Pebesma
>>>>> Institute for Geoinformatics (ifgi), University of M?nster Weseler
>>> Stra?e
>>>>> 253, 48151 M?nster, Germany. Phone: +49 251 8333081, Fax: +49 251
>>> 8339763
>>>>> http://ifgi.uni-muenster.de http://www.52north.org/geostatistics
>>>>> e.pebesma at wwu.de
>>>>>
>>>>> _______________________________________________
>>>>> R-sig-Geo mailing list
>>>>> R-sig-Geo at stat.math.ethz.ch
>>>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>>>>>
>>>>>
>>>
>>> --
>>> Edzer Pebesma
>>> Institute for Geoinformatics (ifgi), University of M?nster
>>> Weseler Stra?e 253, 48151 M?nster, Germany. Phone: +49 251
>>> 8333081, Fax: +49 251 8339763 http://ifgi.uni-muenster.de
>>> http://www.52north.org/geostatistics e.pebesma at wwu.de
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 10
>>> Date: Tue, 26 Jan 2010 18:31:00 -0200 (BRST)
>>> From: Paulo Justiniano Ribeiro Jr <paulojus at c3sl.ufpr.br>
>>> To: Edzer Pebesma <edzer.pebesma at uni-muenster.de>
>>> Cc: r-sig-geo at stat.math.ethz.ch
>>> Subject: Re: [R-sig-Geo] maxdist for kriging with an external drift
>>> Message-ID: <alpine.DEB.1.10.1001261822570.28905 at dalmore.c3sl.ufpr.br>
>>> Content-Type: text/plain; charset="iso-8859-1"; Format="flowed"
>>>
>>> May be worth adding here that, despite algorithms and the
>>> "funny naming conventions" (good descrition Edzer!)
>>> SK and others are diferent in the following way:
>>>
>>> SK, as described in Edzer post, assumes you **know** the mean, in other
>>> words, there is no uncertainty about it.
>>> On the other hand, variants such as OK, UK, KED, SKlm uses (explicitly
>>> or implicitly) estimated means.
>>> Therefore, such uncertainty has to be propagated and reflected in the
>>> predictions.
>>>
>>> Suposse the fixed mean in SK is the same as the (implicitly) estimated by
>>> OK. The point predictions will be the same, however, the uncertainty
>>> around them will not (and should not) refleting the uncertainty (or lack
>>> of it) in the process mean.
>>> The prediction variance expressions for SK ond OK will reflect this
>>> whatever the kriging neighborhood is used.
>>>
>>> best
>>> P.J.
>>>
>>> On Tue, 26 Jan 2010, Edzer Pebesma wrote:
>>>
>>>> Oh, geostatistics and its funny naming conventions!
>>>>
>>>> I see local models vs. global models as a completely different modelling
>>>> aspect (model decision, basically) then the SK/OK/UK differences. When
>>>> building on the same tradition / body of literature you quote: in that
>>> case
>>>> KED would be a special form of UK, having only a single non-coordinate
>>>> predictor called 'external drift'.
>>>>
>>>> In my eyes (and that of the literature with more mathematical
>>> statistical
>>>> grounding, such as Cressie 1993 and others), the difference between SK
>>> on the
>>>> one hand and OK/UK on the other is that SK assumes that you know the
>>> mean or
>>>> mean structure. SKlm is then residual kriging added to a known mean
>>> function.
>>>>
>>>> In the gstat R package you obtain SK by specifying a beta value (for the
>>>> mean); SKlm by specifying one or more predictors and passing the (known)
>>>> regression coefficients as beta; you obtain OK/UK by not specifying
>>> beta; a
>>>> formula ending on ~1 results in OK with an unknown mean only.
>>>>
>>>> Ah, and then SK = simple kriging, OK = ordinary kriging, UK = universal
>>>> kriging.
>>>> --
>>>> Edzer
>>>>
>>>> Cutberto Uriel Paredes Hern?ndez wrote:
>>>>> Dear Edzer,
>>>>>
>>>>> Would it be correct to say then that if a neighbourhood is specified
>>>>> in the krige command the result would be that of Kriging with an
>>>>> External Drift (KED), otherwise it would be that of Simple Kriging
>>>>> with varying local means (SKlm)?
>>>>>
>>>>> Apologies for posting on this thread but I was about to post a
>>>>> similiar question.
>>>>>
>>>>> Thanks, Cutberto.
>>>>>
>>>>> 2010/1/26 Edzer Pebesma <edzer.pebesma at uni-muenster.de>:
>>>>>
>>>>>> Yes, that is right.
>>>>>>
>>>>>> Els Verfaillie wrote:
>>>>>>
>>>>>>> Dear list,
>>>>>>>
>>>>>>>
>>>>>>> I want to use Kriging with an external drift for a sedimentological
>>>>>>> dataset
>>>>>>> of grain-size that has a linear relation with the depth.
>>>>>>> Am I correct that when I set a 'maxdist' using the krige command,
>>> that a
>>>>>>> trend for the primary variable (grain-size) is calculated as a local
>>>>>>> linear
>>>>>>> function of the secondary variable (depth)? Is this function thus
>>>>>>> different
>>>>>>> for each interpolation window?
>>>>>>>
>>>>>>> d50.ked.dir50 <- krige(D50F~depth, locations=ds50, newdata=Depth,
>>>>>>> model=d50.fit.var.50, nmin=2, nmax=16, maxdist=9000)
>>>>>>>
>>>>>>>
>>>>>>> Thank you for your help.
>>>>>>>
>>>>>>>
>>>>>>> Best regards,
>>>>>>>
>>>>>>> Els Verfaillie
>>>>>>>
>>>>>>>
>>>>>>> ______________________________________________
>>>>>>>
>>>>>>> Dr. Els Verfaillie
>>>>>>>
>>>>>>> Carto-GIS cluster
>>>>>>>
>>>>>>> Ghent University (UGent) - Department of Geography
>>>>>>>
>>>>>>> ______________________________________________
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> [[alternative HTML version deleted]]
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> R-sig-Geo mailing list
>>>>>>> R-sig-Geo at stat.math.ethz.ch
>>>>>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>>>>>>>
>>>>>>>
>>>>>> --
>>>>>> Edzer Pebesma
>>>>>> Institute for Geoinformatics (ifgi), University of M?nster Weseler
>>> Stra?e
>>>>>> 253, 48151 M?nster, Germany. Phone: +49 251 8333081, Fax: +49 251
>>> 8339763
>>>>>> http://ifgi.uni-muenster.de http://www.52north.org/geostatistics
>>>>>> e.pebesma at wwu.de
>>>>>>
>>>>>> _______________________________________________
>>>>>> R-sig-Geo mailing list
>>>>>> R-sig-Geo at stat.math.ethz.ch
>>>>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>>>>>>
>>>>>>
>>>>
>>>> --
>>>> Edzer Pebesma
>>>> Institute for Geoinformatics (ifgi), University of M?nster Weseler
>>> Stra?e
>>>> 253, 48151 M?nster, Germany. Phone: +49 251 8333081, Fax: +49 251
>>> 8339763
>>>> http://ifgi.uni-muenster.de http://www.52north.org/geostatistics
>>>> e.pebesma at wwu.de
>>>>
>>>> _______________________________________________
>>>> R-sig-Geo mailing list
>>>> R-sig-Geo at stat.math.ethz.ch
>>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>>>>
>>>
>>> Paulo Justiniano Ribeiro Jr
>>> LEG (Laboratorio de Estatistica e Geoinformacao)
>>> Universidade Federal do Parana
>>> Caixa Postal 19.081
>>> CEP 81.531-990
>>> Curitiba, PR - Brasil
>>> Tel: (+55) 41 3361 3573
>>> Fax: (+55) 41 3361 3141
>>> e-mail: paulojus AT ufpr br
>>> http://www.leg.ufpr.br/~paulojus
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 11
>>> Date: Tue, 26 Jan 2010 22:53:15 -0500
>>> From: "rusers.sh" <rusers.sh at gmail.com>
>>> To: r-sig-geo at stat.math.ethz.ch
>>> Subject: [R-sig-Geo] Convert grids with 0/1 attribute to polygons with
>>> neighbor grids of same values merged
>>> Message-ID:
>>> <a835c81e1001261953w69656b0cg3400793f92a4a412 at mail.gmail.com>
>>> Content-Type: text/plain
>>>
>>> Dear all,
>>> Somebody has discussed the similar question before, "converting grid
>>> objects to spatial polygon objects and export as shapefile (
>>> https://stat.ethz.ch/pipermail/r-sig-geo/2009-December/007163.html)",
>>> where
>>> they have successfully convert the grids into spatial polygons. But the
>>> generated polygons didnot merge any original grids.
>>> Now, i have a grid dataset, its attribute is 0/1 variable. So finally i
>>> hope to get two shape files, one is its attribute being 0, another
>>> is attribute being 1. But particularly, i hope to merge the grids if their
>>> attribute's values are same, so the final polygon maybe irregular,which is
>>> different from the previous post. Note each shape files may have several
>>> polygons after merging because the grids with same value are not all in
>>> the
>>> similar positions. That means i only want to merge those close grids with
>>> same value in adjacent positions, and not expect to generate a big polygon
>>> with some holes in it.The main problem maybe how to merge those adjacent
>>> grids with same values into polygons.
>>> #Example data
>>> gt <- GridTopology(c(0.05,0.05), c(0.1,0.1), c(10,10))
>>> xv<-rnorm(length(coordinates(gt)[,1]))
>>> xvs<-ifelse(xv>0.2,1,0)
>>> grd <- SpatialGridDataFrame(gt,
>>> data.frame(xvs),proj4string=CRS(as.character(NA)))
>>> grdM<-as.matrix(data.frame(coordinates(grd),grd at data))
>>> grdM[1:5,]
>>> Any ideas on this? I'd appreciate any suggestions or help.
>>> Thanks.
>>>
>>> --
>>> -----------------
>>> Jane Chang
>>> Queen's
>>>
>>> [[alternative HTML version deleted]]
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 12
>>> Date: Tue, 26 Jan 2010 23:26:18 -0500
>>> From: "rusers.sh" <rusers.sh at gmail.com>
>>> To: Alexandre Villers <alexandre.villersav at laposte.net>
>>> Cc: r-sig-geo at stat.math.ethz.ch
>>> Subject: Re: [R-sig-Geo] complement part of a polygon in another
>>> polygon
>>> Message-ID:
>>> <a835c81e1001262026ub45a630v8bad1297a756771b at mail.gmail.com>
>>> Content-Type: text/plain
>>>
>>> intersect.owin() works for intersection.
>>> Say polygon B located inside A. Is there any function in R for us to get
>>> the complement part of B in polygon A?
>>>
>>> 2010/1/26 Alexandre Villers <alexandre.villersav at laposte.net>
>>>
>>>> Good morning,
>>>>
>>>> You can have a look at union.owin() and intersection.owin() in spatstat.
>>>> You just need to convert from so objects to spatstat object and back...
>>>> Best regards
>>>>
>>>> Alex
>>>>
>>>>
>>>
>>>
>>> --
>>> -----------------
>>> Jane Chang
>>> Queen's
>>>
>>> [[alternative HTML version deleted]]
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 13
>>> Date: Tue, 26 Jan 2010 23:06:41 -0900
>>> From: Martin Renner <martin.renner at stonebow.otago.ac.nz>
>>> To: r-sig-geo at stat.math.ethz.ch
>>> Subject: [R-sig-Geo] kriging as fish swim, not as crows fly
>>> Message-ID:
>>> <498D5289-7BAA-4D6E-BE6B-F202895BFEF2 at stonebow.otago.ac.nz>
>>> Content-Type: text/plain; charset=us-ascii
>>>
>>> Hi All,
>>>
>>> I want to kirg fish and seabird densities within an estuary which has
>>> several arms. Since neither organisms cross land, the appropriate distances
>>> would not be euclidian but over-water (as fish swim). There are several
>>> papers, describing this problem and how to deal with it (see below), but I
>>> have not found an easily accessible implementation. Is anybody aware of a
>>> solution in R?
>>>
>>> Best,
>>> Martin
>>>
>>>
>>>
>>> @article{Rathbun:1998aa,
>>> Author = {Rathbun, Stephen L.},
>>> Journal = {Environmetrics},
>>> Number = {2},
>>> Pages = {109--129},
>>> Title = {Spatial modelling in irregularly shaped regions: kriging
>>> estuaries},
>>> Volume = {9},
>>> Year = {1998}}
>>>
>>> @article{Little:1997aa,
>>> Author = {Little, Laurie S. and Edwards, Don and Porter, Dwayne
>>> E.},
>>> Journal = {Journal of Experimental Marine Biology and Ecology},
>>> Number = {1},
>>> Pages = {1--11},
>>> Title = {Kriging in estuaries: as the crow flies, or as the fish
>>> swims?},
>>> Volume = {213},
>>> Year = {1997}}
>>>
>>>
>>>
>>>
>>> Martin Renner
>>> US Geological Survey
>>> Alaska Science Center
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 14
>>> Date: Wed, 27 Jan 2010 10:17:12 +0100
>>> From: Karl Ove Hufthammer <karl at huftis.org>
>>> To: r-sig-geo at stat.math.ethz.ch
>>> Subject: Re: [R-sig-Geo] Distance to (nearest) polygon
>>> Message-ID: <MPG.25ca23071e15ccd89896d4 at news.gmane.org>
>>> Content-Type: text/plain; charset="us-ascii"
>>>
>>> On Tue, 26 Jan 2010 16:27:23 +0100 (CET) Roger Bivand
>>> <Roger.Bivand at nhh.no> wrote:
>>>
>>>>> For example, I need the distance between points at sea to the nearest
>>>>> land area (as defined by for example the 'world' dataset).
>>>>
>>>> There are methods for point to line segment distances in spatstat.
>>>> Further, for projected (planar) coordinates, this could be added to
>>>> R-Forge rgeos; for geographical coordinates Boost ggl would be needed.
>>>
>>> Thanks. The 'nncross' function in 'spatstat' does essentially do what I
>>> need. Unfortunately, I work with geographical coordinates (spanning
>>> about 15 degrees of latitude), so the results are not perfect (using
>>> plain long/lat coordinates), but they will probably be an adequate
>>> approximation.
>>>
>>> BTW, for my application, I'm not interested in the distance per se, only
>>> in the points (e.g., boats) within a certain distance from the polygon
>>> (land). So I have also thought about a possible solution of using an
>>> expanded polygon, expanded in a certain number of kilometers outwards,
>>> and then using point-in-polygon (i.e., 'overlay') to find the points
>>> that are inside this new polygon. But I couldn't find a function to
>>> 'grow' a polygon in this way.
>>>
>>> --
>>> Karl Ove Hufthammer
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 15
>>> Date: Wed, 27 Jan 2010 20:29:15 +1100
>>> From: Michael Sumner <mdsumner at gmail.com>
>>> To: Martin Renner <martin.renner at stonebow.otago.ac.nz>
>>> Cc: r-sig-geo at stat.math.ethz.ch
>>> Subject: Re: [R-sig-Geo] kriging as fish swim, not as crows fly
>>> Message-ID:
>>> <522664f81001270129g2a80ea2n62e8e6c3442fc7e at mail.gmail.com>
>>> Content-Type: text/plain; charset=UTF-8
>>>
>>> Not kriging as such, but check out the soap-film smoothing in package
>>> mgcv:
>>>
>>> http://www.maths.bath.ac.uk/~sw283/simon/papers/soap.pdf
>>>
>>> FWIW, there are binning methods with MCMC in the package
>>> tripEstimation that have similar features, but they are particularly
>>> focussed on individual track estimation and probably not easily
>>> applied. Is location uncertainty a big issue for your data? What are
>>> the input locations?
>>>
>>> Cheers, Mike.
>>>
>>>
>>> On Wed, Jan 27, 2010 at 7:06 PM, Martin Renner
>>> <martin.renner at stonebow.otago.ac.nz> wrote:
>>>> Hi All,
>>>>
>>>> I want to kirg fish and seabird densities within an estuary which has
>>> several arms. Since neither organisms cross land, the appropriate distances
>>> would not be euclidian but over-water (as fish swim). There are several
>>> papers, describing this problem and how to deal with it (see below), but I
>>> have not found an easily accessible implementation. Is anybody aware of a
>>> solution in R?
>>>>
>>>> Best,
>>>> Martin
>>>>
>>>>
>>>>
>>>> @article{Rathbun:1998aa,
>>>> ? ? ? ?Author = {Rathbun, Stephen L.},
>>>> ? ? ? ?Journal = {Environmetrics},
>>>> ? ? ? ?Number = {2},
>>>> ? ? ? ?Pages = {109--129},
>>>> ? ? ? ?Title = {Spatial modelling in irregularly shaped regions: kriging
>>> estuaries},
>>>> ? ? ? ?Volume = {9},
>>>> ? ? ? ?Year = {1998}}
>>>>
>>>> @article{Little:1997aa,
>>>> ? ? ? ?Author = {Little, Laurie S. and Edwards, Don and Porter, Dwayne
>>> E.},
>>>> ? ? ? ?Journal = {Journal of Experimental Marine Biology and Ecology},
>>>> ? ? ? ?Number = {1},
>>>> ? ? ? ?Pages = {1--11},
>>>> ? ? ? ?Title = {Kriging in estuaries: as the crow flies, or as the fish
>>> swims?},
>>>> ? ? ? ?Volume = {213},
>>>> ? ? ? ?Year = {1997}}
>>>>
>>>>
>>>>
>>>>
>>>> Martin Renner
>>>> US Geological Survey
>>>> Alaska Science Center
>>>>
>>>> _______________________________________________
>>>> R-sig-Geo mailing list
>>>> R-sig-Geo at stat.math.ethz.ch
>>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>>>>
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> _______________________________________________
>>> R-sig-Geo mailing list
>>> R-sig-Geo at stat.math.ethz.ch
>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>>>
>>>
>>> End of R-sig-Geo Digest, Vol 77, Issue 24
>>> *****************************************
>>>
>>
>>
>>
>> --
>> With Kind Regards,
>>
>> oooO:::::::::
>> (..):::::::::
>> :\.(:::Oooo::
>> ::\_)::(..)::
>> :::::::)./:::
>> ::::::(_/::::
>> :::::::::::::
>> [***********************************************************************]
>> ZhiJie Zhang ,PhD
>> Dept.of Epidemiology, School of Public Health,Fudan University
>> Office:Room 443, Building 8
>> Office Tel./Fax.:+86-21-54237410
>> Address:No. 138 Yi Xue Yuan Road,Shanghai,China
>> Postcode:200032
>> Email:epistat at gmail.com <Email%3Aepistat at gmail.com>
>> Website: www.statABC.com
>> [***********************************************************************]
>> oooO:::::::::
>> (..):::::::::
>> :\.(:::Oooo::
>> ::\_)::(..)::
>> :::::::)./:::
>> ::::::(_/::::
>> :::::::::::::
>>
>
>
>
>
--
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
More information about the R-sig-Geo
mailing list