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ReQL command: circle

Command syntax

r.circle([longitude, latitude], radius[, {numVertices: 32, geoSystem: 'WGS84', unit: 'm', fill: true}]) → geometry
r.circle(point, radius[, {numVertices: 32, geoSystem: 'WGS84', unit: 'm', fill: true}]) → geometry

Description

Construct a circular line or polygon. A circle in RethinkDB is a polygon or line approximating a circle of a given radius around a given center, consisting of a specified number of vertices (default 32).

The center may be specified either by two floating point numbers, the latitude (−90 to 90) and longitude (−180 to 180) of the point on a perfect sphere (see Geospatial support for more information on ReQL’s coordinate system), or by a point object. The radius is a floating point number whose units are meters by default, although that may be changed with the unit argument.

Optional arguments available with circle are:

• numVertices: the number of vertices in the polygon or line. Defaults to 32.
• geoSystem: the reference ellipsoid to use for geographic coordinates. Possible values are WGS84 (the default), a common standard for Earth’s geometry, or unit_sphere, a perfect sphere of 1 meter radius.
• unit: Unit for the radius distance. Possible values are m (meter, the default), km (kilometer), mi (international mile), nm (nautical mile), ft (international foot).
• fill: if true (the default) the circle is filled, creating a polygon; if false the circle is unfilled (creating a line).

Example: Define a circle.

r.table('geo').insert({
id: 300,
name: 'Hayes Valley',
neighborhood: r.circle([-122.423246,37.779388], 1000)
}).run(conn, callback);

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