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|Split/Divide Polygons with Polylines using ET GeoWizards|
Many questions similar to the one below have been asked on the ArcGIS forums:
"I am trying to divide county polygons into pieces, and I want to divide it using a road. (i.e. make 2 polygons out of each county, 1 which is north of I-80, and one which is south of I-80, which goes through all of the counties in my dataset). Seems like a relatively simple operation, but I can't figure out how to do it with ArcMap Editor. I thought I'd be able to do this with the GeoProcessing wizard, but I can't, since one is a line shapefile, and one is a polygon shapefile."
Some of the answers (the only ones that gave some sort of a solution) were as follows:
select the polygon to be split
The answer above might do the job, but ONLY if a road goes through the whole county without having an intersection with another road. In other words you need a single polyline that has its ends out of the polygon to be split in order to use the above mentioned approach.
How do you feel about using the above procedure for splitting all the counties in a state with each road of the road network - ONE BY ONE ? Another question is how successful this will be - not that many roads cross a county without intersecting another road.
This document describes a procedure that will help you to split a polygon dataset with a polyline dataset using an ArcView license and the functions available in ET GeoWizards.
Note that the links above are to the functions available via the interface of ET GeoWizards. If the procedure is to be performed in the Model Builder - refer to the corresponding tools available in the ET GeoWizards ToolBox. If performed via a VBA script - refer to ET GeoWizards Scripting
We have four US counties and the highway network in the same area. The goal is to split (divide) the county polygons based on the highway network.
We have the original polygons (counties) and the polylines to be used for splitting (highways). What if instead of trying to split the county polygons with the highway polylines we go a step back - get the counties boundaries (Polylines), merge them with the highways (Polylines) and use the merged dataset to build a brand new polygon dataset. Then we can get the original attributes from the County polygons to the resulting dataset with a simple Spatial Join. The Process step by step:
See ET GeoWizards User Guide for more information
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