r.width.funct - GRASS GIS manual

Note: This document is for an older version of GRASS GIS that has been discontinued. You should upgrade, and read the current manual page.

NAME

r.width.funct - Calculates the Width Function of a watershed basin.

KEYWORDS

raster, hydrology

SYNOPSIS

r.width.funct

r.width.funct --help

r.width.funct map=name image=image [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

--overwrite: Allow output files to overwrite existing files
--help: Print usage summary
--verbose: Verbose module output
--quiet: Quiet module output
--ui: Force launching GUI dialog

Parameters:

map=name [required]: Distance to outlet map (from r.stream.distance)
image=image [required]: Name for output graph file (png)

DESCRIPTION
- Input
- Output
EXAMPLE
- Dependencies
SEE ALSO
REFERENCES
AUTHORS

DESCRIPTION

r.width.funct produces the Width Function of a basin. The Width Function W(x) gives the number of the cells in a basin at a flow distance x from the outlet (it is also referred as distance-area function). It is important to underline the fact that the distance is not the euclidean one, but it is measured along the flowpath towards the outlet.

g.region raster=elevation -p

# Calculate flow direction
r.stream.extract elevation=elevation threshold=1000 \
direction=direction 

# Create outlet point 
echo "637304.924954,218617.100523" | v.in.ascii input=- sep=',' out=outlet

# Convert outlet point to raster
v.to.rast input=outlet type=point output=outlet use=cat

# Calculate distance to outlet map
r.stream.distance -o stream_rast=outlet \
direction=direction distance=dist2out

# Calculate width function
r.width.funct map=dist2out image=/tmp/my_basin

Dependencies

Matplotlib

REFERENCES

Rodriguez-Iturbe I., Rinaldo A. — Fractal River Basins, Chance and Self-Organization. Cambridge Press (2001)
In Italian: Di Leo M., Di Stefano M., Claps P., Sole A. — Caratterizzazione morfometrica del bacino idrografico in GRASS GIS (Morphometric characterization of the catchment in GRASS GIS environment), Geomatics Workbooks, n. 9 (2010)

AUTHORS

Margherita Di Leo (grass-dev AT lists DOT osgeo DOT org), Massimo Di Stefano, Francesco Di Stefano

SOURCE CODE

Available at: r.width.funct source code (history)

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