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
DESCRIPTION
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.
EXAMPLE
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
SEE ALSO
d.what.rast, d.what.vect, v.rast.stats, v.vect.stats, v.what.rast, v.what.rast3, v.what.vect
AUTHOR
Trevor Wiens
Edmonton, Alberta, Canada
SOURCE CODE
Available at: v.what source code (history)
Accessed: Monday Feb 24 17:51:26 2025
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