{% apibody %} r.circle(r.array(longitude, latitude), radius) → geometry r.circle(point, radius) → geometry {% endapibody %}

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 that can be specified with optArg are:

• num_vertices: the number of vertices in the polygon or line. Defaults to 32.
• geo_system: 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(
    r.hashMap("id", 300)
     .with("name", "Hayes Valley")
     .with("neighborhood", r.circle(r.array(-122.423246, 37.779388), 1000))
).run(conn);