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POLYGONSA POLYGONS file type can be used by a thematic or cadastral map. However, when there are polygons in map for both models, the lines behave like islands. The figure below shows two polygons imported from a file of this type, where visually the common line for both polygons are not perceived, but keep in mind that in the polygons adjacency there is a line duplication.
![]() The first line of the file is the keyword POLYGONS. This line starts the identification section, which is a mandatory section. For the POLYGONS entity the information section is not mandatory. The general format of the ASCII file for the POLYGONS entity is presented in the next example.
The first line of the file is the keyword POLYGONS. This line is the identification
section, which is mandatory. For this entity the information section is not mandatory, thus
the following options are available:
The end of each polygon is marked by the keyword END, and the sequence END END shows the end of the data section in the file. There is no constraint related to the number of instances in a file. The lines can represent linear features, or areas (polygons) formed by closing lines, that is islands. A polygon file of a thematic map is the same as a cadastral, the only difference is if the (POINTS) identification file associated to it is used to identify the thematic classes or the cadastral objects. The general format of the ASCII file for the POLYGONS entity is presented in the next example. Notice that the starting and ending coordinates for each polygon are the same, defining the island closing.
NOTE: By default when exporting a polygon file the file name extension is "spr", added to the suffix"_POL" to the IL name, that is, *_POL.spr. However, when importing, if the file was generated by a different system, it has to have the "spr" extension in the file name. The user should select the "Polig. and Identif." option in the>" Exporting" window. Besides the *_POL.spr file it will be created the file *.LAB.spr (POINTS type), as in the "Lines and Identif." option.
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