SDTS (.ddf)
Background
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Import and Export
- Import["dir","SDTS"] or Import["dir"] imports an entire SDTS directory and returns a combined rendering of all graphics layers.
- Import["fileCATD.ddf"] explicitly specifies the main .ddf file of an SDTS bundle to be imported.
- Import["dir"] returns a GeoGraphics object.
- Import["dir","elem"] imports the specified element from an SDTS file.
- Import["dir",{"elem","suba","subb",…}] imports a subelement.
- Import["dir",{{"elem1","elem2",…}}] imports multiple elements.
- See the reference pages for full general information on Import.
Elements
- General Import elements:
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"Elements" list of elements and options available in this file "Rules" full list of rules for each element and option "Options" list of rules for options, properties, and settings - Data representation elements:
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"Graphics" all layers combined into a single graphics object "GraphicsList" list of graphics representing the layers of an SDTS archive "Data" graphics primitives for each layer "SpatialRange" range of geographic coordinates, typically given in decimal degrees - Import by default uses the "Graphics" element for SDTS bundles.
- Import with element "Graphics" gives the combined graphics contents of an SDTS archive as a Graphics or GeoGraphics object.
- Data representation elements:
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"LayerNames" labels for each layer, given as a list of strings "LayerTypes" SDTS data types for each layer - Elements representing the geodetic datum and reference ellipsoid used in the file:
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"CoordinateSystem" name of the coordinate system used in the file "Datum" geodetic datum "SemimajorAxis" semimajor axis of the reference ellipsoid in meters "SemiminorAxis" semiminor axis of the reference ellipsoid in meters "InverseFlattening" inverse flattening of the ellipsoid "LinearUnits" coordinate system units - Elements specifying the cartographic projection and its parameters:
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"Projection" projection name and parameters "Centering" latitude and longitude defining the origin of the projection "StandardParallels" standard parallels "CentralScaleFactor" scale factor at the central meridian or center of projection "GridOrigin" grid coordinates {n,e} of the central parallel and meridian "ProjectionName" Wolfram Language standard name of the projection used "ReferenceModel" what reference sphere or ellipsoid to use - Accessing low-level meta-information from the file:
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"CoordinateSystemInformation" raw parameters of the coordinate system as stored in the file - See the reference page for GeoProjectionData for full information on cartographic projections.
Options
- General rendering options:
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Background None background color ImageSize Automatic overall size of the image
Examples
See Also
Related Guides
Introduced in 2002
(4.2)
| Updated in 2008 (7.0)