0

I want to interpolate some daily point data. The ultimate goal is to receive something like a heat map/IDW map with some interpolation statistics like kriging/IDW.

My data:

Nr.  : coordinates :  Sensor_Name : X04.Apr : X15.Apr : X01.Mai :  X16.Mai : X01.Jun : X16.Jun : X01.Jul

1     (16.623, 48.21022)  Wst_cz3_024      22      21      26      33      30      19      18
2     (16.623, 48.21022)  Wst_cz2_041      24      23      34      38      35      21      19
3     (16.623, 48.21022)  Wst_cz1_019      27      26      30      40      36      23      21
4   (16.62026, 48.21169)  Wst_at3_022      30      28      32      38      36      24      21
5   (16.62026, 48.21169)  Wst_at2_008      28      26      30      36      34      22      20
6   (16.62026, 48.21169)  Wst_at1_001      30      28      27      36      34      24      17
7   (16.62104, 48.21312) Scint2_3_013      15      13      16      26      18       4       6
8   (16.62104, 48.21312) Scint2_2_032      24      22      23      31      28      18      14
9     (16.623, 48.21022) Scint2_1_029      32      30      35      40      37      24      21
.
.
.
.
136 (16.62036, 48.20904)    Ru104_005      20      18      34      42      38      20      17
137 (16.62246, 48.21033)    Ru103_070      19      19      33      40      36      22      20
138   (16.621, 48.20857)    Ru103_057      22      21      35      42      39      24      22

The current code.

#load data#
kriging<-fread(...)
options(max.print=1000000)

min_LON = min(kriging$LON)
min_LAT = min(kriging$LAT)
LON_length = max(kriging$LON - min_LON)
LAT_length = max(kriging$LAT - min_LAT)
cellsize = 50
ncol = round(LON_length/cellsize, 0)
nrow = round(LAT_length/cellsize, 0)
            
coordinates(kriging) = ~LON+LAT
proj4string(kriging) = CRS("+proj=longlat +ellps=WGS84 +datum=WGS84")
head(kriging[,c(1,3,4,5,6,7,8,9)], 138)

Probably the problem is cellsize, ncol and nrow. How would I know how big my cellsize should be? Unfortunately I am stuck with this last part of code. I cant figure out how to finish my goal.

grid = GridTopology(cellcentre.offset = c(min_LON,min_LAT), cellsize = c(cellsize, cellsize), cells.dim = c(ncol,nrow))

The error I get is:

Error in validObject(.Object) : 
  invalid class “GridTopology” object: cells.dim has incorrect dimension
grid = SpatialPixelsDataFrame(grid,
                              data=data.frame(id=1:prod(ncol,nrow)),
                              proj4string=CRS(proj4string(kriging)))
plot(grid)


##autokriging
kriging_result = autoKrige(X04.Apr~1, kriging, kriging.grid)
plot(kriging_result)

I tried to follow the instructions according to this post: 'https://gis.stackexchange.com/questions/158021/plotting-map-resulted-from-kriging-in-r/164421'

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.