r.northerness.easterness - GRASS GIS manual

Note: This addon document is for an older version of GRASS GIS that will be discontinued soon. You should upgrade your GRASS GIS installation, and read the current addon manual page.

NAME

r.northerness.easterness - Calculation of northerness, easterness and the interaction between northerness and slope

KEYWORDS

raster, terrain, aspect, slope, sun

SYNOPSIS

r.northerness.easterness

r.northerness.easterness --help

r.northerness.easterness elevation=name [--help] [--verbose] [--quiet] [--ui]

Flags:

--help: Print usage summary
--verbose: Verbose module output
--quiet: Quiet module output
--ui: Force launching GUI dialog

Parameters:

elevation=name [required]: Name of elevation raster map

DESCRIPTION
NOTES
EXAMPLE
SEE ALSO
REFERENCES
AUTHOR

DESCRIPTION

r.northerness.easterness calculates northerness, easterness and the interaction between northerness and slope (northerness*slope). The user must specify the input elevation raster map.

As aspect is a circular land-surface parameter, in ecology a sine or cosine transformation is often used to obtain a continuous gradient, stressing the north-south or east-west gradient (northness or eastness).

The GRASS GIS default aspect angles (cartesian) are converted to compass angles.

Calculated raster maps are:

northerness: cos(aspect)
easterness: sin(aspect)
interaction between northerness and slope: northerness*slope

The color of these raster maps are set to grey.

EXAMPLE

  # align region to DEM and habitat vector
  g.region -a raster=DEM align=DEM

  # run r.northerness.easterness
  r.northerness.easterness elevation=DEM

REFERENCES

Olaya, V. 2009. Basic Land-Surface Parameters. In: Hengl, T. & Reuter, H.I. (eds.) 2009. Geomorphometry. Concepts, Software, Applications. Developments in Soil Science, Volume 33. Elsevier.

AUTHOR

Helmut Kudrnovsky

SOURCE CODE

Available at: r.northerness.easterness source code (history)

Latest change: Mon Jun 28 07:54:09 2021 in commit: 1cfc0af029a35a5d6c7dae5ca7204d0eb85dbc55