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NAME
v.kernel - Generates a raster density map from vector points data using a moving 2D isotropic Gaussian kernel or optionally generates a vector density map on vector network with a 1D kernel.
KEYWORDS
vector, kernel density
SYNOPSIS
v.kernel
v.kernel help
v.kernel [-oqv] input=name [net=name] output=name stddeviation=float [dsize=float] [segmax=float] [distmax=float] [mult=float] [--verbose] [--quiet]
Flags:
- -o
- Try to calculate an optimal standard deviation with 'stddeviation' taken as maximum (experimental)
- -q
- Only calculate optimal standard deviation and exit (no map is written)
- -v
- Run verbosely
- --verbose
- Verbose module output
- --quiet
- Quiet module output
Parameters:
- input=name
- Input vector with training points
- net=name
- Input network vector map
- output=name
- Output raster/vector map
- stddeviation=float
- Standard deviation in map units
- dsize=float
- Discretization error in map units
- Default: 0.
- segmax=float
- Maximum length of segment on network
- Default: 100.
- distmax=float
- Maximum distance from point to network
- Default: 100.
- mult=float
- Multiply the density result by this number
- Default: 1.
DESCRIPTION
Generates a raster density map from vector points data using
a moving 2D isotropic Gaussian kernel or
optionally generates a vector density map on vector network
with a 1D kernel.
NOTES
The mult option is needed to overcome the limitation that
the resulting density in case of a vector map output is stored as category
(Integer). The density result stored as category may be multiplied by this number.
With the -o flag (experimental) the command tries to calculate an
optimal standard deviation. The value of stddeviation is taken
as maximum value. Standard deviation is calculated using ALL points,
not just those in the current region.
LIMITATIONS
The modules only considers the presence of point, but not
(yet) any attribute values.
SEE ALSO
v.surf.rst
AUTHOR
Stefano Menegon, ITC-irst, Trento, Italy
Radim Blazek (network part)
Last changed: $Date: 2005-01-11 02:23:39 -0800 (Tue, 11 Jan 2005) $
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