Topics: hexagon, square, rectangle, triangle, repeat, sample, tessellation, array, matrix, lattice, point, systematic, grid, extent

Author: Jeff Jenness

Wildlife Biologist, GIS Analyst Jenness Enterprises 3020 N. Schevene Blvd. Flagstaff, AZ, 86004 USA (928) 607-4638 jeffj@jennessent.com

Description: Researchers and land managers often require a way to systematically divide the landscape into equal-sized portions. Breaking up the landscape this way simplifies monitoring plans, and is an essential step in developing systematic sampling designs.

This tool generates an array of repeating shapes over a user-specified area. These shapes can be hexagons, squares, rectangles, triangles, circles or points, and they can be generated with any directional orientation.

Shapes can be generated over all selected records of a feature theme, over the entire rectangular extent of a theme, over the rectangular extent of all themes in the view, or over the rectangular extent of the display.

For those who have access to ArcView 3.x, this extension can be used in conjunction with the “Random Point Generator” extension (http://www.jennessent.com/arcview/random_points.htm) to generate random points within a systematically divided sampling area. This extension can be used to generate systematic polygons over the landscape, and the “Random Point Generator” extension can then be used to generate random sample points within those polygons.



Output: This extension produces either a point or a polygon feature class and adds it as a theme to the view.