The Fractal Realizer May 25, 2007 The Fractal Realizer has been rewritten in Fortran-90. There are no longer any pieces of code in C. The visualization feature (using DrawPixmap) has been eliminated, since maps can be viewed as XPM files after running the model. The new code has been compiled and tested with gfortran under Linux on an Athlon-64 box. Example scripts and data are available in directories below examples/. The code is in the src/ directory. The previous README file is still included here as README.previous. Installation ------------ If you are using gfortran under Linux, simply do the following to build and install the Fractal Realizer. Download the code and examples: $ wget http://www.geobabble.org/~hnw/frdist.90 Then extract the code and examples: $ tar xvzf frdist90.tar.gz Next, build the code: $ cd frdist90/src $ make This will produce the binary program called realizer. To install the Fractal Realizer in /usr/local/bin: $ sudo make install Execution --------- The Fractal Realizer has many options, and some of these are mutually exclusive. Simply running the executable begins a cascade of questions from the model which query the user to set up the options for the simulation run. Responses to the questions direct the subsequent questions, changing the way that the option tree is traversed. This verbose interaction mode is a good way to become familiar with the wide array of Fractal Realizer options. After all questions are answered, the simulation begins. Because answering all of the input questions for each run would be tedious, the Fractal Realizer writes a script file, inpout.scr, containing the input answers from the last run. Thus, the last simulation can be repeated by issuing the command: $ realizer < input.scr To change a few input settings, it is not necessary to wade through all of the input questions again. Instead, simply edit the input.scr script file directly, and then re-run the simulation using the modified script file. Mnemonic comments within the script file aid in such editing process. A number of demonstration .scr script files are included in the in the examples/ directory, and running these "canned" examples is a good way to test the installation, as well as to see the capabilities of the Fractal Realizer. Final landscapes and tie maps can be output in several formats, including XPM and GRASS. The FR program uses a heap sort to sort the entire map to find the highest probability sites, so execution time will increase rapidly as the size of the map is increased. Execution time also increases with increasing numbers of categories in the map. Because of the midpoint displacement algorithm for generating (pseudo)fractals, the maps must be square, with sides of (2**n)+1. However, the use of constraint masks will permit oddly-shaped and smaller synthetic maps to be generated while still preserving both p and the fractal dimension of each category. The Fractal Realizer has proven useful and stimulating. Be sure to read and cite our paper in Conservation Ecology available at http://www.ecologyandsociety.org/vol6/iss1/art2/ Bill and Forrest ------------------------------------------------------------------------------- William W. Hargrove Eastern Forest Environmental Threat Assessment Center USDA Forest Service Southern Research Station 200 WT Weaver Boulevard Asheville, NC 28804-3454 ------------------------------------------------------------------------------- Forrest Hoffman mailto:forrest@climatemodeling.org Oak Ridge National Laboratory mailto:forrest@computer.org Climate & Carbon Research Institute http://www.climatemodeling.org/~forrest Computer Science & Mathematics Div. (865) 576-7680 voice Building 5600, Room C221, MS 6016 (865) 576-5491 fax P.O. Box 2008 Deliveries: Bethel Valley Road Oak Ridge TN 37831-6016 35� 55' 23" N 84� 19' 20" W -------------------------------------------------------------------------------