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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

v.stream.network - Build a linked stream network: each link knows its downstream link

KEYWORDS

vector, stream network, hydrology, geomorphology

SYNOPSIS

v.stream.network
v.stream.network --help
v.stream.network map=name [upstream_easting_column=string] [upstream_northing_column=string] [downstream_easting_column=string] [downstream_northing_column=string] [tostream_cat_column=string] [--help] [--verbose] [--quiet] [--ui]

Flags:

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

Parameters:

map=name [required]
Vector stream network from r.stream.extract
Or data source for direct OGR access
upstream_easting_column=string
Upstream easting (or x or lon) column name
Default: x1
upstream_northing_column=string
Upstream northing (or y or lat) column name
Default: y1
downstream_easting_column=string
Downstream easting (or x or lon) column name
Default: x2
downstream_northing_column=string
Downstream northing (or y or lat) column name
Default: y2
tostream_cat_column=string
Adjacent downstream segment cat (0 = offmap flow)
Default: tostream

Table of contents

DESCRIPTION

v.stream.network populates the attribute table of a river network built by r.stream.extract with five new columns that define the nodes and links within a river network. These are (default names given):

NOTES

streams is a set of vector lines that is generated by r.stream.extract. It is recommended to be built as follows (Python code):
# Choose elevation map and threshold
elevation = srtm
threshold = 1E6 # [m**2], minimum catchment size = 1 km**2
# Build a map of cell areas: pick one of these
# km2 is more intuitive, but 1 km2 is the threshold for the smallest
# threshold catchment size
r.mapcalc('cellArea_meters2 = '+str(reg.nsres)+' * '+str(reg.ewres), overwrite=True)
r.mapcalc("cellArea_km2 = cellArea_meters2 / 10^6", overwrite=True)

# Use r.watershed to build a drainage basin with units of length**2
# instead of arbitrary units (cells)
r.watershed(elevation=elevation, flow='cellArea_meters2', accumulation='drainageArea_m2', drainage='drainageDirection', stream='streams', threshold=thresh, flags='s', overwrite=True)
# Note that this will include areas of negative (i.e. offmap) flow accumulation

# Build watershed network using r.stream.extract: single-flow-direction (SFD)
print "Building drainage network"
r.stream_extract(elevation=elevation, accumulation='drainageArea_m2', threshold=thresh, d8cut=0, mexp=0, stream_raster='streams', stream_vector='streams', direction='draindir', overwrite=True)

SEE ALSO

r.stream.extract v.stream.order

REFERENCES

None (yet)

AUTHOR

Andrew D. Wickert

SOURCE CODE

Available at: v.stream.network source code (history)

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


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.

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© 2003-2022 GRASS Development Team, GRASS GIS 7.8.8dev Reference Manual