NAME
v.what - Queries a vector map at given locations.
KEYWORDS
vector,
querying,
position
SYNOPSIS
v.what
v.what --help
v.what [-dagjm] map=name[,name,...] [layer=string[,string,...]] [type=string[,string,...]] coordinates=east,north [distance=float] [columns=name[,name,...]] [--help] [--verbose] [--quiet] [--ui]
Flags:
- -d
- Print topological information (debugging)
- -a
- Print attribute information
- -g
- Print the stats in shell script style
- -j
- Print the stats in JSON
- -m
- Print multiple features if overlapping features are found
- --help
- Print usage summary
- --verbose
- Verbose module output
- --quiet
- Quiet module output
- --ui
- Force launching GUI dialog
Parameters:
- map=name[,name,...] [required]
- Name of vector map(s)
- layer=string[,string,...]
- Layer number or name ('-1' for all layers)
- A single vector map can be connected to multiple database tables. This number determines which table to use. When used with direct OGR access this is the layer name.
- Default: -1
- type=string[,string,...]
- Input feature type
- Options: point, line, boundary, centroid, area, face, kernel
- Default: point,line,area,face
- coordinates=east,north [required]
- Coordinates for query
- '-' for standard input
- distance=float
- Query threshold distance
- Default: 0
- columns=name[,name,...]
- Name of attribute column(s)
- Default: all columns
v.what outputs the category number value(s) associated with
user-specified location(s) in user-specified vector map layer(s).
This module was derived from the
d.what.vect module by
removing all interactive code and modification of the output for
easy parsing. Using the
-g flag generates script-style
output which is easily parsable.
North Carolina sample dataset example:
Query polygon at given position:
v.what zipcodes_wake coordinates=637502.25,221744.25
Find closest hospital to given position within given distance (search radius):
v.what hospitals coordinates=542690.4,204802.7 distance=2000000
d.what.rast,
d.what.vect,
v.rast.stats,
v.vect.stats,
v.what.rast,
v.what.rast3,
v.what.vect
Trevor Wiens
Edmonton, Alberta, Canada
SOURCE CODE
Available at:
v.what source code
(history)
Latest change: Thursday Jan 26 14:10:26 2023 in commit: cdd84c130cea04b204479e2efdc75c742efc4843
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GRASS Development Team,
GRASS GIS 8.3.3dev Reference Manual