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Polygon in planar coordinates

A `mappolyshape`

object represents a polygon or multipolygon in
planar 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 geographic coordinates, use a `geopolyshape`

object
instead.

To create `mappolyshape`

objects, either:

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

`readgeotable`

function, and then query the`Shape`

variable of the table.Use the

`mappolyshape`

function (described here).

`shape = mappolyshape(`

creates a `x`

,`y`

)`mappolyshape`

object or array of `mappolyshape`

objects with vertices at the specified *x*- and
*y*-coordinates. The sizes of `x`

,
`y`

, and the `mappolyshape`

object array
`shape`

match.

The `mappolyshape`

function assumes that `x`

and
`y`

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.