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] [--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

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

AUTHOR

Trevor Wiens

Edmonton, Alberta, Canada

Last changed: $Date: 2014-10-22 12:22:22 +0200 (Wed, 22 Oct 2014) $

SOURCE CODE

Available at: v.what source code (history)