Grapher imports elevation data in the form of a uniform lattice from SDTS Digital Elevation Model .DEM data sets.
There are two separate types of SDTS DEM files. The Topological Vector Profile SDTS files contain boundary line information and can be used with File | Import.
The Raster Profile SDTS files contain gridded elevation information and can be used to directly create a grid-based map such as a contour map. An uncompressed SDTS contains several files with the .DDF extension. All of the .DDF files are necessary to produce a map (i.e. you cannot copy just one .DDF file and create a map from it). You can choose any of the .DDF files when importing a base map with the Topological Vector Profile SDTS files.
Formats Supported for Import
2D uniform lattice; 8-, 16-, 32-bit integer, float, double
Import Options Dialog
No import options dialog is displayed.
Import Automation Options
No import options are available.
Export Options Dialog
Grapher does not currently support SDTS export.