I am trying to use autoKrige in automap package. My data looks like
head(LL12)
Location Longitude Latitude percent
1 L1 16.48476 -28.60737 1.0000000
2 L3 16.90045 -29.24154 1.0000000
3 L4 16.99268 -28.44906 0.6363636
4 L5 17.06871 -29.67825 1.0000000
5 L6 17.09935 -29.00169 0.6000000
6 L7 17.25630 -28.82418 1.0000000
and I am trying to plot this in a South African map.
First I obtained the grid following Create Grid in R for kriging in gstat
SAgrd <- makegrid(SApol_border, n = 1000)
colnames(SAgrd) <- c('lon','lat')
SAgrd_pts <- SpatialPoints(coords = SAgrd,
proj4string=CRS(proj4string(SApol_border)))
SAgrd_pts_in <- SAgrd_pts[SApol_border, ]
plot(SAgrd_pts_in)
plot(SAgrd_pts_in)
then I convert it to a SpatialPixel dataframe
SAgrd_pts_in = as(SAgrd_pts_in,"SpatialPixelsDataFrame")
but plot(SAgrd_pts_in) gives the follwoing error message:
Error in .subset2(x, i, exact = exact) : subscript out of bounds
and when I want to use the following line in autokriging also gives error message
krigLL12_fit <- autoKrige(percent~1, SA.grid, LL12spdf) # percent is the variable of interest in the spdf LL12spdf
error message:
Error in autoKrige(percent ~ 1, SA.grid, LL12spdf) : Either input_data or new_data is in LongLat, please reproject. input_data: +proj=longlat +ellps=WGS84 +towgs84=0,0,0,0,0,0,0 +no_defs new_data: NA In addition: Warning messages: 1: In proj4string(input_data) : CRS object has comment, which is lost in output 2: In proj4string(input_data) : CRS object has comment, which is lost in output 3: In showSRID(uprojargs, format = "PROJ", multiline = "NO") : Discarded datum Unknown based on WGS84 ellipsoid in CRS definition, but +towgs84= values preserved
I am very new in this topic and cannot realize what I need to do, or what to correct, the coordinate units look the same in the grid and in the data file. I also fitted an autovariogram and tried to use in in autokrige but it doean't work either. thnx.
