sp

Thanks a lot for the reply Prof. Bivand. It works fine now. Yes I did 
not use R since few months.I was wondering why this piece of coding left 
is not working: neighbors.knn1 <- knn2nb(knearneigh(coord, 1, 
longlat=F), sym=F)## Global G dlwknn1.B <- nb2listw(neighbors.knn1, 
style="B", zero.policy=TRUE) globalG.test(CRIME, dlwknn1.B, 
zero.policy=F)

Error: object 'CRIME' not found

Thanks again for your help.Francesco

? ? Il gioved? 16 maggio 2019, 15:07:37 CEST, Roger Bivand <Roger.Bivand at nhh.no> ha scritto:

Please post in plain text to avoid code mangling. You have not noticed
that a lot has been happening. First, data sets from spdep have mostly
been moved to spData. Next, spData mostly uses sf to read and format data.
Finally you may also see changes as spdep model fitting functions are in
spatialreg and will shortly be dropped from spdep. In your case:

library(sp)
library(spdep)

Loading required package: spData
Loading required package: sf
Linking to GEOS 3.7.2, GDAL 3.0.0, PROJ 6.1.0

example(columbus)

colmbs> columbus <- st_read(system.file("shapes/columbus.shp",
package="spData")[1], quiet=TRUE)

colmbs> col.gal.nb <- read.gal(system.file("weights/columbus.gal",
package="spData")[1])

coord <- coordinates(columbus)

Error in (function (classes, fdef, mtable)? :
? unable to find an inherited method for function ?coordinates? for
signature ?"sf"?

columbus <- as(columbus, "Spatial")
coord <- coordinates(columbus)

Giving the full output, you can see that example(columbus) reads in the
data and neighbours from spData, using sf. Consequently, you'd need to
coerce columbus to an sp class if you do not want to upgrade your
workflow to sf compatability.

Hope this clarifies,

Roger

On Thu, 16 May 2019, Francesco Perugini via R-sig-Geo wrote:

Dear all,I'm not very familiar with R.
I'm tying to use this code I've written months ago. At that time it was
working but now it is not.

library(sp)
library(spdep)
example(columbus)
coord <- coordinates(columbus)and get this message

Error in (function (classes, fdef, mtable)? : unable to find an
inherited method for function ?coordinates? for signature ?"sf"?
I've tried to also calllibrary(sf)but got the same error.I was wondering
why?
Thanks a lot.Francesco



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