Module to reshape vectors. The reshape operation includes the
possibility to:
- add one or more new columns to the vector table attribute
- convert the geometry into a derived geometry (from polygons to
points or to lines)
- delete from the vector table attribute
The reshape uses the ECQL language, please refer to the
uDig user manual or the
GeoTools documentation for more informations about the syntax and
usability of the language.
Geometry changing examples:
To create a centroid layer from a polygon layer use:
the_geom=centroid(the_geom)
To create a buffer of 20 meters from a points layer use:
the_geom=buffer(the_geom, 20.0)
To create a convex hull from a points layer use:
the_geom=convexHull(the_geom)
Other examples:
To create a two new field containing the perimeter and area of the
polygons in a layer:
area=area(the_geom)
length=geomLength(the_geom)
This is also the perfect way to create a new column in a shapefile
layer and assign it a new default value:
newfield=-1
Inputs
- the vector to reshape
- the ECQL reshape function
- the list of fields to remove, comma separated
Output