Dear list, We are working on an agent-based simulation of agricultural production in the Pampas of Argentina. Very briefly, we want to ask the list for tips about how to divide a polygon (e.g., a county, or administrative division) into several smaller polygons of different sizes. Each of the smaller polygons would represent the geographic boundaries of one simulated farm (or pseudo-farm).
A more detailed explanation of the problem We are modifying the space (or environment) of our agent-based model from a regular grid to a GIS space. In the current regular grid, each point in the grid represents a simulated farm. In the GIS space, a farm will be represented by a polygon describing its geographic boundaries. We have a shape file describing the contour of a county (or administrative division); this county is the area to model. However, we do NOT have actual cadastre information with the boundaries of all farms inside the county. What we do have is information from the Argentine Agricultural Census containing: (a) the number of farms (N) inside the county (this is the _approximate_ number of farms we want to simulate) and (b) a frequency distribution of farm sizes in the county (e.g., 45 farms with areas from 50 to 99 hectares, 30 farms between 100 and 150 hectares, and so on ). Also, we can create a vector of N simulated sizes by using the size frequency information in the Census and sampling inside each size interval (e.g., if the Census says there are 3 farms between 500 and 1000 hectares, we can simulate their sizes as 536, 777 and 900 hectares). Using the information above, we would like to create approx. N simulated farms (or pseudo-farms) inside the county of interest, including their boundaries. I guess another way of framing the question is to say we want to fit N polygons of different sizes inside a larger polygon (that represents the county where farms are located). A couple of details that may help: (a) N does not have to be exactly the number in the census (i.e., plus or minus 2-3% does not matter), (b) we do not have to fill the entire county with farms (empty areas can represent cities, forests, etc), although the "non-farm" area cannot be huge. Is there any way of doing this using the R spatial libraries? Suggestions or pointers are most welcome and we thank in advance all readers of the list Regards! ---------------------------------------------------------------------- ------------------------------- Guillermo P. Podestá University of Miami Rosenstiel School of Marine & Atmospheric Science 4600 Rickenbacker Causeway Miami FL 33149-1098, USA E-mail: [email protected] Voice: +1.305.421.4142 Fax: +1.305.421.4622 http://www.rsmas.miami.edu/divs/mpo/people/Faculty/Podesta/index.htm _______________________________________________ R-sig-Geo mailing list [email protected] https://stat.ethz.ch/mailman/listinfo/r-sig-geo
