r.pi.odc

Omnidirectional connectivity analysis

r.pi.odc [-abdm] input=name output=name [mask=string] keyval=integer ratio=string stats=string [,string,...] [neighbor_level=integer] [title="phrase"] [--overwrite] [--verbose] [--quiet] [--qq] [--ui]

Example:

r.pi.odc input=name output=name keyval=integer ratio=string stats=string

grass.script.run_command("r.pi.odc", input, output, mask=None, keyval, ratio, stats, neighbor_level=None, title=None, flags=None, overwrite=False, verbose=False, quiet=False, superquiet=False)

Example:

gs.run_command("r.pi.odc", input="name", output="name", keyval=integer, ratio="string", stats="string")

Parameters

Command linePython (grass.script)

input=name [required]
    Name of input raster map
output=name [required]
    Name for output raster map
mask=string
    Name of a raster file with a mask (0,1 values)
keyval=integer [required]
    Category value of the patches
ratio=string [required]
    Compensation method to perform on the values
    Allowed values: none, odd_area, area_odd, odd_perim, perim_odd
stats=string [,string,...] [required]
    Statistical method to perform on the values
    Allowed values: average, variance, standard deviation, median
neighbor_level=integer
    Level of neighbors to analyse
title="phrase"
    Title for resultant raster map
-a
    Set for 8 cell-neighbors. 4 cell-neighbors are default
-b
    Allow moving on diagonals
-d
    Graphical output
-m
    Adjacency matrix output
--overwrite
    Allow output files to overwrite existing files
--help
    Print usage summary
--verbose
    Verbose module output
--quiet
    Quiet module output
--qq
    Very quiet module output
--ui
    Force launching GUI dialog

input : str, required
    Name of input raster map
    Used as: input, raster, name
output : str, required
    Name for output raster map
    Used as: output, raster, name
mask : str, optional
    Name of a raster file with a mask (0,1 values)
    Used as: input, raster
keyval : int, required
    Category value of the patches
ratio : str, required
    Compensation method to perform on the values
    Allowed values: none, odd_area, area_odd, odd_perim, perim_odd
stats : str | list[str], required
    Statistical method to perform on the values
    Allowed values: average, variance, standard deviation, median
neighbor_level : int, optional
    Level of neighbors to analyse
title : str, optional
    Title for resultant raster map
    Used as: "phrase"
flags : str, optional
    Allowed values: a, b, d, m
    a
        Set for 8 cell-neighbors. 4 cell-neighbors are default
    b
        Allow moving on diagonals
    d
        Graphical output
    m
        Adjacency matrix output
overwrite: bool, optional
    Allow output files to overwrite existing files
    Default: False
verbose: bool, optional
    Verbose module output
    Default: False
quiet: bool, optional
    Quiet module output
    Default: False
superquiet: bool, optional
    Very quiet module output
    Default: False

DESCRIPTION

r.pi.odc is part of the patch based fragmentation analysis package r.pi.* (Patch Index). It computes omnidirectional connectivity analysis between patches.

NOTES

Several output raster are generated with the defined output file name and a suffix of the information provided. All files named *.FP.* are providing information concerning the focus patch. All files named *.TP.* are providing informaton about the target patches.
...

The user must specify the names of the raster map layers to be used for input and output, the keyval the ratio (area/odd or odd/area) and stats used (i.e., average).

Within r.pi.odc the following setting have to be set:

keyval setting

The keyval operator determines which category value is taken for the Patch Index analysis.

Ratio setting

The ratio operators determine what measure is applied.

Neighbourhood level

The neighbor_level operator determines which neighbourhood level is used. 0 produces output for the focus patch itself, 1 assigns the connectivity information of the first omnidirectional neighbours to the focus patch, hence the connectivity of the surrouding fragments. This value can be increased for analysing the more distant neighbours.

Output

Various output files are autmatically created with the pattern $output.* The ... FP describes attributes of the fokus patch (area and area of the odd) TP describes attributes of the target patch (all neighbouring patches around the FP) - separated by the statsmethod (average, median, variance, stddev) ratio describes which ratio is taken for all TPs. The output raster files are named accordingly:
*.FP.area: size of the patch
*.FP.odd: size of the isolation area
*.FP.odd_area: ratio of size of patch and size of isolaton area
*.TP.no: amount of neighbouring patches
*.TP.area.avg: average size of all neighbouring patches
*.TP.odd.avg: average size of all isolation areas of neighbouring patches
*.TP.odd_area.avg: average ratio of isolation area to patch size
*.diagram: (if flag -d active) isolation areas and border are depicted

EXAMPLE

An example for the North Carolina sample dataset:

r.pi.odc input=landclass96 output=odc keyval=5 ratio=odd_area stats=average neighbor_level=0 -d

AUTHORS

Programming: Elshad Shirinov
Scientific concept: Dr. Martin Wegmann
Department of Remote Sensing
Remote Sensing and Biodiversity Unit
University of Wuerzburg, Germany

Port to GRASS GIS 7: Markus Metz

SOURCE CODE

Available at: r.pi.odc source code (history)
Latest change: Friday Feb 21 12:27:42 2025 in commit 8fce680