Hi List, I'm not sure what I'm doing wrong here and would appreciate some help. I create a NetCDF dataset as follows: library(ncdf) combined.ncdf <- with(new.env(), { nLat <- 7 nLon <- 8 nTime <- 9 missing.val <- -999 filename <- file.path(tempdir(), 'combined_d6fg4s64s6g4l.nc') lat.dim <- dim.def.ncdf('lat', 'degrees', 1:nLat) lon.dim <- dim.def.ncdf('lon', 'degrees', 1:nLon) time.dim <- dim.def.ncdf("time", "days since 1970-01-01", as.integer(1:nTime), unlim=T) var.def <- var.def.ncdf('Data', 'mm', list(lon.dim, lat.dim, time.dim), missing.val, prec='single') nc <- create.ncdf(filename, var.def) for(i in 1:nLon) for(j in 1:nLat) for(k in 1:nTime) put.var.ncdf(nc, var.def, i + j*10 + k*100, c(i, j, k), rep(1, 3)) nc }) the following do not work: get.var.ncdf(combined.ncdf) get.var.ncdf(combined.ncdf, varid='Data') get.var.ncdf(combined.ncdf, varid=4) all of which I thought would be equivalent and would give me the same as: get.var.ncdf(combined.ncdf, forcevarid=4) Could someone please point out the error of my ways. Thanx in advance, Simon Knapp R version: 2.14.1, ncdf built with version: 2.14.2 os: windows 7 [[alternative HTML version deleted]]