Sorry, dlat is what changes an example file can be found at
http://www.ocean.udel.edu/CMS/moliver/20071003.276.0237.n17.nc use require(ncdf) f <- open.ncdf("20071003.276.0237.n17.nc"<http://www.ocean.udel.edu/CMS/moliver/20071003.276.0237.n17.nc> ) lon <- get.var.ncdf(f, "lon") lat <- get.var.ncdf(f, "lat") Thanks in advance Matt On Thu, Jul 31, 2008 at 5:03 PM, Michael Sumner <[EMAIL PROTECTED]>wrote: > You can use gdalwarp in FWTools to re-grid the data with control points > (perhaps with with some effort), but as you say that will interpolate to a > regular grid. > > Is it definitely dlon that increases? Can you post a link to an example > file? > > Some netCDF files I've seen are actually using Mercator, but store the > pixel coordinates as lon/lat. > > There are totally irregular grids as well though, so as a raster you would > have to resample it in some way. Otherwise you can interpret the data as a > SpatialPointsDataFrame and use it as you would in Matlab. Note that the > image() function will handle irregular (but xy locked) grid spacings, so you > can jig a function to plot these things as an image pretty easily. > > Cheers, Mike. > > > Matt Oliver wrote: > >> Hi All, I have CF compliant ncdf files of sea surface temperature. The >> lon, >> lat grid is known but not equally spaced (ie dlon increases). Is there a >> clean way to get this matrix ported over to a geo-tiff or some other file >> that Arc will read? I have talked with some arc users that tell me that >> the >> grid needs to be equally spaced. I guess I could interpolate to an equally >> spaced grid, but I would rather preserve the original grid if possible. >> >> Thanks in advance >> >> Matt >> >> >> >> > > -- Matthew J. Oliver Assistant Professor College of Marine and Earth Studies University of Delaware 700 Pilottown Rd. Lewes, DE, 19958 302-645-4079 http://www.ocean.udel.edu/people/profile.aspx?moliver [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo