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PDW
A program for rescaling map resolution. The method uses a general approach to either increase resolution (finer grain sizes) or decrease resolution (aggregation). The method involves: 1) sampling of the existing map with a point-centered, distance-weighted window; 2) creating a cumulative frequency distribution of cover types from the sampled area; and 3) randomly selecting the cover type for the new map from this cumulative frequency distribution. This process is iterated for all grid elements of the new map.
PDW is written in fortran-90 for execution under Windows or LINUX. The Open Software License (http://www.opensource.org/licenses/index.php) applies to the distribution, use, and possible alteration of PDW.
Documentation:
How PDW works – PDWdocumentation.pdf
Executables:
Executable for Windows – PDWdos.zip
Executable for LINUX – PDWlinux.zip
Example input/output files:
Maps, input scripts, + example output – PDWinout.zip
Source code:
Fortran source code – PDWcode.zip
Publications:
Gardner, R. H., T. R. Lookingbill, P. A. Townsend, and J. Ferrari. 2008. A new approach for the analysis of multiple resolution landscape imagery. Landscape Ecology.

