Running examples in ‘GSIF-Ex.R’ failed
The error most likely occurred in:

> ### Name: gstatModel-class
> ### Title: A class for a geostatistical model
> ### Aliases: gstatModel-class validate,gstatModel-method
> ###   plot,gstatModel,ANY-method validate print.gstatModel plot.gstatModel
> ### Keywords: classes
> 
> ### ** Examples
>  
> ## load observations:
> library(plotKML)
plotKML version 0.6-1 (2020-03-08)
URL: http://plotkml.r-forge.r-project.org/
> library(sp)
> library(maptools)
Checking rgeos availability: TRUE
> demo(meuse, echo=FALSE)
Warning in showSRID(uprojargs, format = "PROJ", multiline = "NO", prefer_proj = prefer_proj) :
  Discarded datum Amersfoort in Proj4 definition
> data(meuse)
> coordinates(meuse) <- ~x+y
> proj4string(meuse) <- CRS("+init=epsg:28992")
Warning in showSRID(uprojargs, format = "PROJ", multiline = "NO", prefer_proj = prefer_proj) :
  Discarded datum Amersfoort in Proj4 definition
> ## load grids:
> data(meuse.grid)
> coordinates(meuse.grid) <- ~x+y
> gridded(meuse.grid) <- TRUE
> proj4string(meuse.grid) <- CRS("+init=epsg:28992")
Warning in showSRID(uprojargs, format = "PROJ", multiline = "NO", prefer_proj = prefer_proj) :
  Discarded datum Amersfoort in Proj4 definition
> ## fit a model:
> omm <- fit.gstatModel(meuse, om~dist+ffreq, 
+   fit.family=gaussian(link="log"), meuse.grid)
Fitting a 2D variogram...
Warning in proj4string(predictionDomain) :
  CRS object has comment, which is lost in output
Warning in proj4string(predictionDomain) :
  CRS object has comment, which is lost in output
Saving an object of class 'gstatModel'...
> plot(omm)
dev.new(): using pdf(file="Rplots11.pdf")
> ## produce SpatialPredictions:
> om.rk <- predict(omm, predictionLocations = meuse.grid)
Warning in proj4string(predictionLocations) :
  CRS object has comment, which is lost in output
Warning in proj4string(object@sp) :
  CRS object has comment, which is lost in output
Subsetting observations to fit the prediction domain in 2D...
Warning in proj4string(observed) :
  CRS object has comment, which is lost in output
Warning in proj4string(predictionLocations) :
  CRS object has comment, which is lost in output
Generating predictions using the trend model (RK method)...
Warning in proj4string(d$data) :
  CRS object has comment, which is lost in output
Warning in proj4string(newdata) :
  CRS object has comment, which is lost in output
[using ordinary kriging]

100% done
Warning in proj4string(newdata) :
  CRS object has comment, which is lost in output
Warning in showSRID(uprojargs, format = "PROJ", multiline = "NO", prefer_proj = prefer_proj) :
  Discarded datum Unknown based on Bessel 1841 ellipsoid in Proj4 definition
Running 5-fold cross validation using 'krige.cv'...
Warning in proj4string(d$data) :
  CRS object has comment, which is lost in output
Warning in proj4string(newdata) :
  CRS object has comment, which is lost in output
Warning in proj4string(newdata) :
  CRS object has comment, which is lost in output
Warning in showSRID(uprojargs, format = "PROJ", multiline = "NO", prefer_proj = prefer_proj) :
  Discarded datum Unknown based on Bessel 1841 ellipsoid in Proj4 definition
Warning in proj4string(d$data) :
  CRS object has comment, which is lost in output
Warning in proj4string(newdata) :
  CRS object has comment, which is lost in output
Warning in proj4string(newdata) :
  CRS object has comment, which is lost in output
Warning in showSRID(uprojargs, format = "PROJ", multiline = "NO", prefer_proj = prefer_proj) :
  Discarded datum Unknown based on Bessel 1841 ellipsoid in Proj4 definition
Warning in proj4string(d$data) :
  CRS object has comment, which is lost in output
Warning in proj4string(newdata) :
  CRS object has comment, which is lost in output
Warning in proj4string(newdata) :
  CRS object has comment, which is lost in output
Warning in showSRID(uprojargs, format = "PROJ", multiline = "NO", prefer_proj = prefer_proj) :
  Discarded datum Unknown based on Bessel 1841 ellipsoid in Proj4 definition
Warning in proj4string(d$data) :
  CRS object has comment, which is lost in output
Warning in proj4string(newdata) :
  CRS object has comment, which is lost in output
Warning in proj4string(newdata) :
  CRS object has comment, which is lost in output
Warning in showSRID(uprojargs, format = "PROJ", multiline = "NO", prefer_proj = prefer_proj) :
  Discarded datum Unknown based on Bessel 1841 ellipsoid in Proj4 definition
Warning in proj4string(d$data) :
  CRS object has comment, which is lost in output
Warning in proj4string(newdata) :
  CRS object has comment, which is lost in output
Warning in proj4string(newdata) :
  CRS object has comment, which is lost in output
Warning in showSRID(uprojargs, format = "PROJ", multiline = "NO", prefer_proj = prefer_proj) :
  Discarded datum Unknown based on Bessel 1841 ellipsoid in Proj4 definition
Creating an object of class "SpatialPredictions"
> plot(om.rk)
> ## run a proper cross-validation:
> rk.cv <- validate(omm)
Estimating the predictionDomain...
Error: 'owin' is not an exported object from 'namespace:spatstat'
Execution halted