[GRASS-stats] another gstat error

[Jarosław Jasiewicz]

Hi
Another gstat error:

var.krigged=krige(z~x+y,gr,grid,model=var.fitted)
[using universal kriging]

"chfactor.c", line 130: singular matrix in function LDLfactor()
Error in predict.gstat(g, newdata = newdata, block = block, nsim = nsim,  :
 LDLfactor

I can't imagine the reason

regards
Jarek

here is structure of my gr spatialPointsDataFrame used in analysis:

str(gr)
Formal class 'SpatialPointsDataFrame' [package "sp"] with 5 slots
 ..@ data       :'data.frame':    2201 obs. of  5 variables:
 .. ..$ cat: num [1:2201] 2 3 4 5 6 7 8 9 10 11 ...
 .. ..$ naz: Factor w/ 874 levels "1000","1001",..: 874 1 2 3 4 5 6 7 8 
9 ...
 .. ..$ x  : num [1:2201] 360175 360176 360178 360169 360167 ...
 .. ..$ y  : num [1:2201] 512736 512736 512733 512719 512712 ...
 .. ..$ z  : num [1:2201] 86.5 87.4 87.7 86.9 86 ...
 ..@ coords.nrs : num(0)
 ..@ coords     : num [1:2201, 1:2] 360175 360176 360178 360169 360167 ...
 .. ..- attr(*, "dimnames")=List of 2
 .. .. ..$ : NULL
 .. .. ..$ : chr [1:2] "coords.x1" "coords.x2"
 ..@ bbox       : num [1:2, 1:2] 359907 512481 360492 512778
 .. ..- attr(*, "dimnames")=List of 2
 .. .. ..$ : chr [1:2] "coords.x1" "coords.x2"
 .. .. ..$ : chr [1:2] "min" "max"
 ..@ proj4string:Formal class 'CRS' [package "sp"] with 1 slots
 .. .. ..@ projargs: chr " +proj=tmerc +lat_0=0 +lon_0=19 +k=0.9993 
+x_0=500000 +y_0=-5300000 +no_defs +a=6378137 +rf=298.257222101 
+towgs84=0.000,0.000,"| __truncated__

and newdata grid:
str(grid)
Formal class 'SpatialGridDataFrame' [package "sp"] with 6 slots
 ..@ data       :'data.frame':    131352 obs. of  1 variable:
 .. ..$ region2: int [1:131352] NA NA NA NA NA NA NA NA NA NA ...
 ..@ grid       :Formal class 'GridTopology' [package "sp"] with 3 slots
 .. .. ..@ cellcentre.offset: Named num [1:2] 359902 512478
 .. .. .. ..- attr(*, "names")= chr [1:2] "x" "y"
 .. .. ..@ cellsize         : num [1:2] 1.001 0.998
 .. .. ..@ cells.dim        : int [1:2] 421 312
 ..@ grid.index : int(0)
 ..@ coords     : num [1:2, 1:2] 359902 360322 512478 512788
 .. ..- attr(*, "dimnames")=List of 2
 .. .. ..$ : NULL
 .. .. ..$ : chr [1:2] "x" "y"
 ..@ bbox       : num [1:2, 1:2] 359901 512477 360323 512789
 .. ..- attr(*, "dimnames")=List of 2
 .. .. ..$ : chr [1:2] "x" "y"
 .. .. ..$ : chr [1:2] "min" "max"
 ..@ proj4string:Formal class 'CRS' [package "sp"] with 1 slots
 .. .. ..@ projargs: chr " +proj=tmerc +lat_0=0 +lon_0=19 +k=0.9993 
+x_0=500000 +y_0=-5300000 +no_defs +a=6378137 +rf=298.257222101 
+towgs84=0.000,0.000,"| __truncated__