I can't reproduce the problem with the meuse data either, so I've uploaded my original data: http://r-sig-geo.2731867.n2.nabble.com/file/n5655660/data_error.RData data_error.RData
I get the problem when I do: library(sp) load("data_error.RData") summary(data_pixels) summary(as(data_pixels,'SpatialGridDataFrame')) Here is the output from sessionInfo: > sessionInfo() R version 2.10.1 (2009-12-14) x86_64-apple-darwin9.8.0 locale: [1] en_GB.UTF-8/en_GB.UTF-8/C/C/en_GB.UTF-8/en_GB.UTF-8 attached base packages: [1] stats graphics grDevices utils datasets methods base other attached packages: [1] sp_0.9-65 loaded via a namespace (and not attached): [1] grid_2.10.1 lattice_0.18-3 -- View this message in context: http://r-sig-geo.2731867.n2.nabble.com/trouble-coercing-SpatialPixelsDataFrame-into-SpatialGridDataFrame-tp5654305p5655660.html Sent from the R-sig-geo mailing list archive at Nabble.com. _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo