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Polygon in geographic coordinates

A `geopolyshape`

object represents a polygon or multipolygon in
geographic coordinates. A *polygon* is a region bounded by a closed curve
and can include interior holes. A *multipolygon* is an individual polygon
shape that includes multiple nonintersecting regions.

To represent a polygon or multipolygon in planar coordinates, use a `mappolyshape`

object
instead.

To create `geopolyshape`

objects, either:

Import polygon data in geographic coordinates as a geospatial table using the

`readgeotable`

function, and then query the`Shape`

variable of the table.Use the

`geopolyshape`

function (described here).

`shape = geopolyshape(`

creates a `lat`

,`lon`

)`geopolyshape`

object or array of `geopolyshape`

objects with vertices at the specified latitude and longitude coordinates. The sizes of
`lat`

, `lon`

, and the
`geopolyshape`

object array `shape`

match.

The `geopolyshape`

function assumes that `lat`

and `lon`

define polygons with valid topology. A polygon has valid
topology when:

Region interiors are to the right as you trace boundaries from vertex to vertex.

The boundaries have no self-intersections.

In general, the outer boundaries of polygons with valid topology have vertices in a clockwise order and the interior holes have vertices in a counterclockwise order.