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Importing ASCII multipolygon features

A MultiPolygon feature is characterised by a set of polygons, whose location and shape is specified by a similar number of point sets, and sharing the same descriptive attributes. The ASCII file may have zero or two header lines. The first headerline must include the ID column name and attribute field names, while the second headerline include the co-ordinate column names. The next lines define the multipolygon features, where each feature is defined with an attribute line, one co-ordinate line for each point defining the multipolygon feature, a number of 'newpart' lines, and an 'end-of-feature' line. The attribute line includes the feature ID and other attribute values for the multipolygon feature. The 'newpart' line just includes the word NEW in the beginning of the line. After reading this line, INSROP GIS interprets the next line as the first point co-ordinate in the next polygon of the multipolygon feature. The 'end-of-feature' line just includes the word END in the beginning of the line. After reading this line, INSROP GIS interprets the next line as the attribute line of the next multipolygon feature. See Example .

To import multipolygon features from an ASCII file, choose the New Theme from ASCII file menu choice in the View menu in the view window.

Note:

If a multipolygon includes overlapping polygons, ArcView interprets the overlap zone as a hole. Unless this is the user's intention, multipolygon features should be created from non-overlapping polygons. For non-overlapping polygons, a multipolygon feature is conceptually similar to an ARC/INFO Region feature.