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NAME

r.li - package overview

DESCRIPTION

The r.li suite is a toolset for multiscale analysis of landscape structure.

How to calculate an index in a raster map:

  1. run r.li.setup: create a configuration file selecting the parts of raster to analyze.
  2. run r.li.'index' (e.g., r.li.patchdensity) for calculate the selected index using on the areas selected on configuration file.

NOTE

Also the r.li.daemon has a main function and it can be run, but it is only a template for development of new indices. The function itself has no meaning, it can be used only for debug.

EXAMPLE

To calculate a patch density index on a whole 'geology' raster map in the Spearfish region, using a 5x5 moving window, follow this procedure:
  1. CREATE A NEW CONFIGURATION FILE
    1. run
              r.li.setup
      
    2. The main r.li.setup window is displayed, click on "New"
    3. Now it is displayed the new configuration window, enter the configuration file name (e.g., "my_conf", do not use absolute paths) and the name of raster map (e.g., "geology"). The other fields are not needed for this configuration.
    4. Click on "Setup sampling frame", select "Whole maplayer" and click "OK"
    5. Click on "Setup sampling areas", select "Moving window" and click "OK"
    6. Click on "Use keyboard to enter moving window dimension"
    7. Select "Rectangle" and enter 5 on "heigth" and "width" fields
    8. Click on "Save settings"
    9. Close r.li.setup window
  2. CALCULATE PATCHDENSITY INDEX
    1. set region settings to geology raster map:
      	g.region rast=geology -p
      
    2. run r.li.patchdensity:
              r.li.patchdensity map=geology conf=my_conf out=patchdens
      
The resulting patch density is stored in "patchdens" raster map. You can verify the result for example with contour lines:
r.contour in=patchdens out=patchdens step=5
d.rast patchdens
d.vect -c patchdens
Note that if you want to run another index with the same area configuration, you don't have to create another configuration file. You can also use the same area configuration file on another map. The program rescale it automatically. For instance if you have selected a 5x5 sample area on 100x100 raster map, and you use the same configuration file on a 200x200 raster map, then the sample area is 10x10.

SEE ALSO

Core modules: Patch indices: Diversity indices:

AUTHORS

Claudio Porta and Lucio Davide Spano, students of Computer Science University of Pisa (Italy).
Commission from Faunalia Pontedera (PI)

BUGS

Please send bugs reports to spano@cli.di.unipi.it, porta@cli.di.unipi.it

Last changed: $Date: 2007/02/16 11:43:14 $


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