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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.concave.hull - Creates a concave hull around points.

KEYWORDS

vector, geometry, alpha shape

SYNOPSIS

v.concave.hull
v.concave.hull --help
v.concave.hull input=name output=name [threshold=float] [--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:

input=name [required]
Input points
Or data source for direct OGR access
output=name [required]
Name for output vector map
threshold=float
Lower values make the hull more concave
Options: 0-10
Default: 7

Table of contents

DESCRIPTION

v.concave.hull creates a concave hull around points. Contrary to a convex hull, a concave hull can describe the shape of a point cloud.

EXAMPLES

Creating a convex and a concave hull

Creating a convex and a concave hull around schools_wake in the North Carolina sample dataset:
v.hull in=schools_wake out=schools_wake_convex
v.concave.hull in=schools_wake out=schools_wake_concave

Convex hull around schools:

convex hull

Concave hull around schools:

concave hull

Creating Alpha shapes

Alpha shapes around points (left: threshold=8; right: threshold=0.5):

Alpha shape threshold=8   Alpha shape threshold=0.5

SEE ALSO

v.hull, v.buffer,, v.kernel

AUTHOR

Markus Metz

SOURCE CODE

Available at: v.concave.hull 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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