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Can a SF object split into multiple point features?
the st_cast method for sf objects can only split geometries, e.g. cast MULTIPOINT into multiple POINT features. In case of splitting, attributes are repeated and a warning is issued when non-constant attributes are assigned to sub-geometries. To merge feature geometries and attribute values, use aggregate or summarise.
How to create spatial polygons from a Dataframe?
I have a dataframe containing the coordinates of a set of polygons. This is how I would convert it to a spatialPolygons (package sp)
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.
Can you cast a SF object to SP?
You can cast an sf object to sp, for packages that don’t yet support sf – I do this a fair bit for raster/polygon interactions. So you could do:
What is the pattern matrix of St _ contains?
The pattern matrix of the ST_Contains predicate states that the interiors of both geometries must intersect and that the interior and boundary of the secondary (geometry b) must not intersect the exterior of the primary (geometry a ). Using ST_Within or ST_Contains identifies only those geometries that fall entirely inside another geometry.
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 does the predicate ST _ Disjoint return?
The ST_Disjoint predicate’s pattern matrix simply states that neither the interiors nor the boundaries of either geometry intersect. See ST_Disjoint for syntax and example. ST_Equals returns 1 or t (TRUE) if two geometries of the same type have identical x,y coordinate values.