I need to build a model or write an algorithm to do this.
here is my cadastral problem: I have plenty of polygons and I need to make a report of coordinations of their vertices. This is pretty easy: I can extract vertices using ArcGIS toolbox and add XY coordinate to each point again using ArcGIS toolbox. However, since each polygon has 20-30 vertices, I need to condense the information. I need to make reports of the most important vertices which define a polygon. The problem here is that these are polygons with irregular shapes. Some can be defined by using 4 points and some require 10 for example. Moreover, my datasets are huge and I definitely need an automated approach to this.
Here is what I thought I have to do:
1) Polygone to vertices > add XY to vertices
2) for each set of polygon vertices use an iterative approach as follows:
2.1) start with 4 vertices
2.2) calculate area
2.3) evaluate area error percentage (area error/correct area = abs(real area-calculated)/correct area)
2.4) if area error < desired threshold (say 0.05)
then end step 2, go to next polygon
else add one vertex, go to 2.2
3) Make a report of selected vertices
However, I have a problem with this. How should I select the correct vertices in step 2.1 and 2.4. For example, a polygon having 20 vertices, may not be defined using 4 of its vertices, while it can be very well defined using another 4 vertices.
I have access to Arcinfo+python, Xtools, and Matlab+Mapping toolbox. I don't know if I have to use Matlab for this problem or not, since I doubt the efficiency of ArcPy in calculation of new polygon areas.