NAME
v.build - Creates topology for vector map.
Optionally also checks for topological errors.
KEYWORDS
vector,
topology,
geometry
SYNOPSIS
v.build
v.build --help
v.build [-e] map=name [error=name] option=string[,string,...] [--overwrite] [--help] [--verbose] [--quiet] [--ui]
Flags:
- -e
- Extensive checks for topological errors
- Perform in-depth checks for topological errors when building topology
- --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]
- Name of vector map
- error=name
- Name for output vector map where erroneous vector features are written to
- option=string[,string,...] [required]
- Build topology or dump topology or indices to standard output
- Options: build, dump, sdump, cdump, fdump
- Default: build
- build: build topology
- dump: write topology to stdout
- sdump: write spatial index to stdout
- cdump: write category index to stdout
- fdump: write feature index to stdout (OGR simple-feature-based formats only)
v.build builds support files for GRASS vector maps. These
support files supply topology and category information including
spatial index that are needed by other GRASS modules.
GRASS is generating these support files automatically, only in rare
cases the user has to (re)build them.
Refer to
vector data processing in GRASS GIS for
more information on GRASS vector data model.
v.build creates support files only for vector maps located in
the user's current mapset. It's not possible to rebuild support files
(
option=build) for vector maps from other mapsets.
In case of errors, the user can optionally generate an error
vector map containing the erroneous vectors for later inspection.
If error vector map is specified, v.build checks:
- isolated boundaries (which are not forming any areas),
- centroids outside of area,
- duplicated centroids.
Extensive checks for topological errors (flag -e) also
includes:
- lines or boundaries of zero length,
- intersecting boundaries, i.e. overlapping areas,
- areas without centroids that are not isles.
Note that
option=build also recreates spatial and category
indices, not only topology. For linked OGR layers
(see
v.external) also feature
index is created.
v.build map=urbanarea option=build
Note that the vector map
urbanarea must be located in the
current mapset.
Dump options print topology, spatial, category or feature index to
standard output. Such information can also be printed for vector maps
from other mapsets. A description of the vector topology is available in
the
GRASS GIS 8 Programmer's Manual,
section "Vector library topology management".
v.build map=urbanarea option=dump
v.build.all,
v.build.polylines,
v.edit,
v.split,
v.support
See also wxGUI vector digitizer.
Dave Gerdes, U.S.Army Construction Engineering Research
Laboratory,
Michael Higgins, U.S.Army Construction Engineering Research Laboratory,
Radim Blazek, ITC-irst, Trento, Italy
SOURCE CODE
Available at:
v.build source code
(history)
Latest change: Tuesday Dec 17 20:17:20 2024 in commit: ab90c5e5a9b668894da360fa97ffd4a51a38931e
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© 2003-2024
GRASS Development Team,
GRASS GIS 8.5.0dev Reference Manual