MarkLogic 12 EA 1 Product Documentation
geo:distance

geo:distance(
   $p1 as cts:point,
   $p2 as cts:point,
   [$options as xs:string*]
) as xs:double

Summary

Returns the distance (in units) between two points.

Parameters

p1 The first point.

p2 The second point.

Parameters
p1	The first point.
p2	The second point.
options	Options for the operation. The default is (). Options include: "coordinate-system=`string`" Use the given coordinate system. Valid values are: wgs84 The WGS84 coordinate system with degrees as the angular unit. wgs84/radians The WGS84 coordinate system with radians as the angular unit. wgs84/double The WGS84 coordinate system at double precision with degrees as the angular unit. wgs84/radians/double The WGS84 coordinate system at double precision with radians as the angular unit. etrs89 The ETRS89 coordinate system. etrs89/double The ETRS89 coordinate system at double precision. raw The raw (unmapped) coordinate system. raw/double The raw coordinate system at double precision. "precision=value" Use the coordinate system at the given precision. Allowed values: `float` and `double`. "units=value" Measure distance and the radii of circles in the specified units. Allowed values: `miles` (default), `km`, `feet`, `meters`.

options

Options for the operation. The default is ().

Options include:

"coordinate-system=string"

Use the given coordinate system. Valid values are:

wgs84
The WGS84 coordinate system with degrees as the angular unit.

wgs84/radians
The WGS84 coordinate system with radians as the angular unit.

wgs84/double
The WGS84 coordinate system at double precision with degrees as the angular unit.

wgs84/radians/double
The WGS84 coordinate system at double precision with radians as the angular unit.

etrs89
The ETRS89 coordinate system.

etrs89/double
The ETRS89 coordinate system at double precision.

raw
The raw (unmapped) coordinate system.

raw/double
The raw coordinate system at double precision.

"precision=value"

Use the coordinate system at the given precision. Allowed values: float and double.

"units=value"

Measure distance and the radii of circles in the specified units. Allowed values: miles (default), km, feet, meters.

Usage Notes

The value of the precision option takes precedence over that implied by the governing coordinate system name, including the value of the coordinate-system option. For example, if the governing coordinate system is "wgs84/double" and the precision option is "float", then the operation uses single precision.

Example

let $sf := cts:point(37, -122)
let $ny := cts:point(40, -73)
return
geo:distance($sf, $ny)

=> 2623.2017796533

Example

xquery version "1.0-ml";
import module namespace op = 'http://marklogic.com/optic' 
           at 'MarkLogic/optic.xqy';
import module namespace ogeo = 'http://marklogic.com/optic/expression/geo' 
           at 'MarkLogic/optic/optic-geo.xqy';

(: Optic example using the Value Processing Function ogeo:distance() :)
let $plan:= op:from-view('buildings', 'builds')
             =>op:bind(op:as('result',ogeo:distance(op:col('interiorPoint'),cts:point('POINT(-98.83211485551952 36.1919336424082)'),'units=miles')))
             =>op:select(('result', op:col('interiorPoint')))
             =>op:order-by('result')

return $plan=>op:result()
(:
==>
rows representing the distance in miles between each point in the 'interiorPoint' column
and the wkt point 'POINT(-98.83211485551952 36.1919336424082)'
sorted by distance
:)

Example

xquery version "1.0-ml";
(: SQL example using ST_Distance() :)
xquery version "1.0-ml";
  xdmp:sql("select ST_Distance(interiorPoint, 'POINT(-98.83211485551952 36.1919336424082)', 'units=feet') from builds order by geoid limit 20")
(:
==>
rows representing the distance in feet between the interiorPoint column
and the WKT point 'POINT(-98.83211485551952 36.1919336424082)'
sorting by geoid
:)

Example

xquery version "1.0-ml";
(: GeoSPARQL example using geof:distance() :)
let $query:=
'
PREFIX my: <http://example.org/ApplicationSchema#>
PREFIX geoml: <http://marklogic.com/geospatial#>
PREFIX cts: <http://marklogic.com/cts#>
PREFIX geof: <http://www.opengis.net/def/function/geosparql/>
 
SELECT *
WHERE { ?s my:hasExactGeometry ?o
  BIND(geof:distance(?o, ''POINT(39.801681875000014 66.64631330892108)'', ''units=km'') as ?distance)
  FILTER BOUND(?distance)
}
ORDER BY ?distance'
return sem:sparql($query)
(:
==>
rows representing the distance in kilometers between each point in a triple's object (if exists)
and the wkt point 'POINT(39.801681875000014 66.64631330892108)'
sorting by distance
:)

MarkLogic 12 EA 1 Product Documentationgeo:distance

Summary

Usage Notes

See Also

Example

Example

Example

Example

MarkLogic 12 EA 1 Product Documentation
geo:distance