Spatialpolygonsdataframe

On Wed, 19 Aug 2015, Metastate Metastate wrote:

Hi

I tried to use sp merge to join the spatialpolygonddataframe (xx) and an
dataframe (yy4), which have 2 observations for each spatial ID. But it did
not allow with an error message as below:
Error in .local(x, y, ...) :  'y' has multiple records for one or more
'by.y' key(s)

I also tried the mapmerge in eeptools but failed.

Any suggestion? Thank you very much.

Meta

Thanks for a reproducible example. Don't use merge() unless you know
already that the objects are conformable:

library("eeptools")
library("sp")
xx <- maptools::readShapePoly(system.file("shapes/sids.shp",
package="maptools")[1], IDvar="FIPSNO")
yy<-as(xx,"data.frame")
yy$newvar<-sample(0:100,nrow(yy),replace=TRUE)
yy<-subset(yy,select=c("FIPS","newvar"))
yy3<-yy
yy3$newvar<-10*yy3$newvar
yy4<-data.frame(rbind(yy,yy3))
newpoly<-merge(xx,yy4,sort=FALSE, by.x="FIPS",
                 by.y="FIPS" ,all.y=TRUE)

Look at str(yy4) and dim(xx) - they are not conformable. Add a "time"
variable and use reshape() to get to a conformable object:

yy4$time <- c(rep(1, 100), rep(2, 100))
yy4a <- reshape(yy4, direction="wide", idvar="FIPS", timevar="time")

str(yy4a)

and combine:

library(maptools)
xxx <- spCbind(xx, yy4a)
summary(xxx)
spplot(xxx, c("newvar.1", "newvar.2"))

Note that the SIDS dataset is already in thw "wide" format with data from
1974 and 1979 as columns. Read up on the long and wide formats, and maybe
look at the documentation of the spacetime package.

Roger

On Tue, Aug 18, 2015 at 7:31 PM, Metastate Metastate <metastate at gmail.com

wrote:

Cool. Let me take a look. Thank you very much, Lo?c.

Meta



On Tue, Aug 18, 2015 at 3:31 AM, Lo?c Dutrieux <loic.dutrieux at wur.nl>
wrote:

Hi,

Have a look at merge in the sp package.
?sp::merge

Cheers,
Lo?c

On 08/18/2015 04:12 AM, Metastate Metastate wrote:

Hi all,

I am starting to learn spatial analysis using R. Do anyone know if the
attribute data in a spatialpolygonsdataframe can contain multiple
observations within the same polygon? To be specific, I have a
spatialpolygonsdataframe that contain USA county polygons and the
relevant
attribute data contains the relevant state,county and FIPs.  And I also
have another data-frame that contains weather features by year by
county
(For example there are yearly average temperature for each county) .
How
can I join the spatialpolygondataframe with the weather data so that
the
resulted attribute table in the joint spatialpolygonsdataframe can
contain
*multiple-year* weather features within each county?

Thank you very much for any kindly help.

Meta

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--
Roger Bivand
Department of Economics, Norwegian School of Economics,
Helleveien 30, N-5045 Bergen, Norway.
voice: +47 55 95 93 55; fax +47 55 95 91 00
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