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How to cast a point to a polygon?
In case to is missing, st_cast.sfc will coerce combinations of “POINT” and “MULTIPOINT”, “LINESTRING” and “MULTILINESTRING”, “POLYGON” and “MULTIPOLYGON” into their “MULTI…” form, or in case all geometries are “GEOMETRYCOLLECTION” will return a list of all the contents of the “GEOMETRYCOLLECTION” objects, or else do nothing.
How to cast geometry from one type to another?
… integer vector, denoting how geometries should be grouped (default: no grouping) logical; if TRUE, group or split geometries; if FALSE, carry out a 1-1 per-geometry conversion. object of class to if successful, or unmodified object if unsuccessful. If information gets lost while type casting, a warning is raised.
What happens if to is specified in St _ Cast?
In case to is specified, if to is “GEOMETRY”, geometries are not converted, else, st_cast will try to coerce all elements into to; ids may be specified to group e.g. “POINT” objects into a “MULTIPOINT”, if not specified no grouping takes place.
What makes a multipolygon instance an accepted polygon?
A MultiPolygon instance is accepted one of the following conditions is met. It is an empty MultiPolygon instance. All instances comprising the MultiPolygon instance are accepted Polygon instances. For more information on accepted Polygon instances, see Polygon. The following examples show accepted MultiPolygon instances.
How to use multipolygon in a list form?
E.g. name =*, source =*. The relations are described in the text in list form making them more readable than XML notation. New members added in the current step to the relation are marked >italic. Relation Tag for Relation Member of Relation >New member of Relation
The numbers and letters in the figures are followed by the tags for the object (way or area) to make the figures rather self-explanatory. Only for the example essential tags are given. Tags which aren’t essential for the examples are omitted. E.g. name =*, source =*.