## Summary

A Polygon object is a closed shape defined by a connected sequence of x,y coordinate pairs.

## Discussion

In many geoprocessing workflows, you may need to run a specific operation using coordinate and geometry information but don't necessarily want to go through the process of creating a new (temporary) feature class, populating the feature class with cursors, using the feature class, then deleting the temporary feature class. Geometry objects can be used instead for both input and output to make geoprocessing easier. Geometry objects can be created from scratch using Geometry, Multipoint, PointGeometry, Polygon, or Polyline classes.

During the creation of a geometry object, a simplification process is performed to make the geometry topologically consistent according to its geometry type. For instance, it rectifies polygons that may be self-intersecting, or contain incorrect ring orientations. Coordinates may move within the resolution of the geometry's spatial reference.

The following numeric operators can be used in place of geometry methods:

Geometry method | Numeric operator |
---|---|

intersect | + |

union | | |

difference | - |

symmetricDifference | ^ |

For example, to union two geometry objects, g3 = g1 | g2 is equivalent to g3 = g1.union(g2).

The + operator will use the geometry type (dimension) of the first geometry to determine the geometry type of the output.

## Syntax

Polygon (inputs, {spatial_reference}, {has_z}, {has_m})

Parameter | Explanation | Data Type |

inputs | The coordinates used to create the object. The data type can be either Point or Array objects. | Object |

spatial_reference | The spatial reference of the new geometry. (The default value is None) | SpatialReference |

has_z | The Z state: True for geometry if Z is enabled and False if it is not. (The default value is False) | Boolean |

has_m | The M state: True for geometry if M is enabled and False if it is not. (The default value is False) | Boolean |

## Properties

Property | Explanation | Data Type |

JSON (Read Only) | Returns an Esri JSON representation of the geometry as a string. ## Tip:The returned string can be converted to a dictionary using the json module's loads function. | String |

WKB (Read Only) | Returns the well-known binary (WKB) representation for OGC geometry. It provides a portable representation of a geometry value as a contiguous stream of bytes. | Bytearray |

WKT (Read Only) | Returns the well-known text (WKT) representation for OGC geometry. It provides a portable representation of a geometry value as a text string. Any true curves in the geometry will be densified into approximate curves in the WKT string. | String |

area (Read Only) | The area of a polygon feature. It is zero for all other feature types. | Double |

centroid (Read Only) | The true centroid if it is within or on the feature; otherwise, the label point is returned. | Point |

extent (Read and Write) | The extent of the geometry. | Extent |

firstPoint (Read Only) | The first coordinate point of the geometry. | Point |

hasCurves (Read Only) | Returns True if the geometry has a curve. | Boolean |

hullRectangle (Read Only) | A space-delimited string of the coordinate pairs of the convex hull rectangle. | String |

isMultipart (Read Only) | Returns True if the number of parts for this geometry is more than one. | Boolean |

labelPoint (Read Only) | The point at which the label is located. The labelPoint is always located within or on a feature. | Point |

lastPoint (Read Only) | The last coordinate of the feature. | Point |

length (Read Only) | The length of the linear feature. The calculation uses 2D Cartesian mathematics. For point and multipoint geometry, the length will be zero. For polygon geometry, the length will be the 2D length of the boundary. | Double |

length3D (Read Only) | The 3D length of the linear feature. The calculation uses 3D Cartesian mathematics. For point and multipoint geometry, the length will be zero. For polygon geometry, the length will be the 3D length of the boundary. ## Caution:The operation does not perform unit conversion between the horizontal and the vertical coordinate systems. The x, y, and z coordinates are assumed to be in the same linear unit. ## Caution:This property is only available for projected data. | Double |

partCount (Read Only) | The number of geometry parts for the feature. | Integer |

pointCount (Read Only) | The total number of points for the feature. | Integer |

spatialReference (Read Only) | The spatial reference of the geometry. | SpatialReference |

trueCentroid (Read Only) | The center of gravity for a feature. | Point |

type (Read Only) | The geometry type: polygon, polyline, point, multipoint, multipatch, dimension, or annotation. | String |

## Method Overview

Method | Explanation |

angleAndDistanceTo (other, {method}) | Returns a tuple of angle and distance to a point or polygon. |

boundary () | Constructs the boundary of the geometry. |

buffer (distance) | Constructs a polygon at a specified distance from the geometry. |

clip (envelope) | Constructs the intersection of the geometry and the specified extent. |

contains (second_geometry, {relation}) | Indicates if the base geometry contains the comparison geometry. contains is the opposite of within. Only True relationships are shown in this illustration. |

convexHull () | Constructs the geometry that is the minimal bounding polygon such that all outer angles are convex. |

crosses (second_geometry) | Indicates if the two geometries intersect in a geometry of a lesser shape type. Two polylines cross if they share only points in common, at least one of which is not an endpoint. A polyline and an polygon cross if they share a polyline or a point (for vertical line) in common on the interior of the polygon which is not equivalent to the entire polyline. Only True relationships are shown in this illustration. |

cut (cutter) | Splits this geometry into a part left of the cutting polyline, and a part right of it. When a polyline or polygon is cut, it is split where it intersects the cutter polyline. Each piece is classified as left of or right of the cutter. This classification is based on the orientation of the cutter line. Parts of the target polyline that do not intersect the cutting polyline are returned as part of the right of result for that input polyline. If a geometry is not cut, the left geometry will be empty (None). |

densify (type, distance, {deviation}) | Creates a new geometry with added vertices. |

difference (other) | Constructs the geometry that is composed only of the region unique to the base geometry but not part of the other geometry. The following illustration shows the results when the red polygon is the source geometry. |

disjoint (second_geometry) | Indicates if the base and comparison geometries share no points in common. Two geometries intersect if disjoint returns False. Only True relationships are shown in this illustration. |

distanceTo (other) | Returns the minimum distance between two geometries. The distance is in the units of the geometry's spatial reference. If the geometries intersect, the minimum distance is 0. Both geometries must have the same projection. |

equals (second_geometry) | Indicates if the base and comparison geometries are of the same shape type and define the same set of points in the plane. This is a 2D comparison only; M and Z values are ignored. Only True relationships are shown in this illustration. |

generalize (max_offset) | Creates a new simplified geometry using a specified maximum offset tolerance. |

getArea ({type}, {units}) | Returns the area of the feature using a measurement type. |

getLength ({measurement_type}, {units}) | Returns the length of the feature using a measurement type. |

getPart ({index}) | Returns an Array object of Point objects for a particular part of the geometry if an index is specified. If an index is not specified, an Array object containing an Array of Point objects for each geometry part is returned. The getPart method is equivalent to indexing an object; that is, obj.getPart(0) is equivalent to obj[0]. |

intersect (other, dimension) | Constructs a geometry that is the geometric intersection of the two input geometries. Different dimension values can be used to create different shape types. The intersection of two geometries of the same shape type is a geometry containing only the regions of overlap between the original geometries. For faster results, test if the two geometries are disjoint before calling intersect. |

overlaps (second_geometry) | Indicates if the intersection of the two geometries has the same shape type as one of the input geometries and is not equivalent to either of the input geometries. Only True relationships are shown in this illustration. |

pointFromAngleAndDistance (angle, distance, {method}) | Returns a point at a given angle in degrees and distance in the units of the geometry's spatial reference using the specified measurement type. |

positionAlongLine (value, {use_percentage}, {geodesic}) | Returns a point on a line at a specified distance from the beginning of the line. |

projectAs (spatial_reference, {transformation_name}) | Projects a geometry and optionally applies a geotransformation. To project, the geometry must have a spatial reference, and not have an unknown coordinate system. The new spatial reference system passed to the method defines the output coordinate system. If either spatial reference is unknown, the coordinates will not be changed. The z- and m-values are not changed by the projectAs method. |

symmetricDifference (other) | Constructs the geometry that is the union of two geometries minus the instersection of those geometries. The two input geometries must be the same shape type. |

touches (second_geometry) | Indicates if the boundaries of the geometries intersect. Two geometries touch when the intersection of the geometries is not empty, but the intersection of their interiors is empty. For example, a point touches a polyline only if the point is coincident with one of the polyline end points. Only True relationships are shown in this illustration. |

union (other) | Constructs the geometry that is the set-theoretic union of the input geometries. The two geometries being unioned must be the same shape type. |

within (second_geometry, {relation}) | Indicates if the base geometry is within the comparison geometry. within is the opposite operator of contains. Only True relationships are shown in this illustration. The base geometry is within the comparison geometry if the base geometry is the intersection of the geometries and the intersection of their interiors is not empty. within is a Clementini operator, except in the case of an empty base geometry. |

## Methods

angleAndDistanceTo (other, {method})

Parameter | Explanation | Data Type |

other | The second geometry. If the geometry is a polygon, the distance is measured to the centroid of the polygon. | PointGeometry |

method | The method used to measure distance. - GEODESIC—The shortest line between any two points on the earth's surface on a spheroid (ellipsoid). One use for a geodesic line is to determine the shortest distance between two cities for an airplane's flight path. This is also known as a great circle line if based on a sphere rather than an ellipsoid.
- GREAT_ELLIPTIC—The line on a spheroid (ellipsoid) defined by the intersection at the surface by a plane that passes through the center of the spheroid and the start and endpoints of a segment. This is also known as a great circle when a sphere is used.
- LOXODROME—The line follows a single compass bearing, or azimuth. Great circle routes are often broken into a series of loxodromes, which simplifies navigation. This is also known as a rhumb line.
- PLANAR—Planar measurements use 2D Cartesian mathematics to calculate lengths and areas. This option is only available when measuring in a projected coordinate system and the 2D plane of that coordinate system will be used as the basis for the measurements. Planar measurements reflect the projection of geographic data onto a 2D surface, and do not account for the curvature of the earth.
- PRESERVE_SHAPE—This type calculates the area or length of the geometry on the surface of the earth ellipsoid, for geometry defined in a projected or geographic coordinate system. This option preserves the shape of the geometry in its coordinate system.
(The default value is GEODESIC) | String |

Data Type | Explanation |

tuple | Returns a tuple of angle (in degrees) and distance (in meters) to another point. |

boundary ()

Data Type | Explanation |

Object | A polygon's boundary is a polyline. A polyline's boundary is a multipoint, corresponding to the endpoints of the line. A point or multipoint's boundary is an empty point or multipoint. |

buffer (distance)

Parameter | Explanation | Data Type |

distance | The buffer distance. The buffer distance is in the same units as the geometry that is being buffered. A negative distance can only be specified against a polygon geometry. | Double |

Data Type | Explanation |

Polygon | The buffered polygon geometry. |

clip (envelope)

Parameter | Explanation | Data Type |

envelope | An Extent object used to define the clip extent. | Extent |

Data Type | Explanation |

Object | An output geometry clipped to the specified extent. |

contains (second_geometry, {relation})

Parameter | Explanation | Data Type |

second_geometry | A second geometry. | Object |

relation | The spatial relationship type. - BOUNDARY— Relationship has no restrictions for interiors or boundaries.
- CLEMENTINI— Interiors of geometries must intersect. Specifying CLEMENTINI is equivalent to specifying None. This is the default.
- PROPER— Boundaries of geometries must not intersect.
(The default value is None) | String |

Data Type | Explanation |

Boolean |
A return Boolean value of True indicates this geometry contains the second geometry. |

convexHull ()

Data Type | Explanation |

Object | The resulting geometry. The convex hull of a single point is the point itself. |

crosses (second_geometry)

Parameter | Explanation | Data Type |

second_geometry | A second geometry. | Object |

Data Type | Explanation |

Boolean | A return Boolean value of True indicates the two geometries intersect in a geometry of a lesser shape type. |

cut (cutter)

Parameter | Explanation | Data Type |

cutter | The cutting polyline geometry. | PolyLine |

Data Type | Explanation |

Geometry | A list of two geometries. |

densify (type, distance, {deviation})

Parameter | Explanation | Data Type |

type | The type of densification, DISTANCE, ANGLE, or GEODESIC. - DISTANCE—Creates a new feature that is a piecewise linear approximation of the input.
- ANGLE—Creates a new feature that is a piecewise linear approximation of the input. Vertices are introduced at points where the angle between tangents at those points is the provided angle.
- GEODESIC—Densifies and reshapes segments between input vertices so that the output segments follow the shortest ground path connecting input vertices.
| String |

distance | The maximum distance between vertices. The actual distance between vertices will usually be less than the maximum distance as new vertices will be evenly distributed along the original segment. If using a type of DISTANCE or ANGLE, the distance is measured in the units of the geometry's spatial reference. If using a type of GEODESIC, the distance is measured in meters. | Double |

deviation | Densify uses straight lines to approximate curves. You use deviation to control the accuracy of this approximation. The deviation is the maximum distance between the new segment and the original curve. The smaller its value, the more segments will be required to approximate the curve. If using a type of DISTANCE, the deviation is measured in the units of the geometry's spatial reference. If using a type of ANGLE, the deviation is measured in radians. If using a type of GEODESIC, the deviation is not used. | Double |

Data Type | Explanation |

Geometry | The densified geometry. |

difference (other)

Parameter | Explanation | Data Type |

other | A second geometry. | Object |

Data Type | Explanation |

Object | The resulting geometry. |

disjoint (second_geometry)

Parameter | Explanation | Data Type |

second_geometry | A second geometry. | Object |

Data Type | Explanation |

Boolean | A return Boolean value of True indicates that the two geometries share no points in common. |

distanceTo (other)

Parameter | Explanation | Data Type |

other | A second geometry. | Object |

Data Type | Explanation |

Double | The distance between the two geometries. |

equals (second_geometry)

Parameter | Explanation | Data Type |

second_geometry | A second geometry. | Object |

Data Type | Explanation |

Boolean |
A return Boolean value of True indicates that the two geometries are of the same shape type and define the same set of points in the plane. |

generalize (max_offset)

Parameter | Explanation | Data Type |

max_offset | The maximum offset tolerance. | Double |

Data Type | Explanation |

Geometry | The generalized geometry. |

getArea ({type}, {units})

Parameter | Explanation | Data Type |

type | The method used to measure area. - GEODESIC—The shortest line between any two points on the earth's surface on a spheroid (ellipsoid). One use for a geodesic line is to determine the shortest distance between two cities for an airplane's flight path. This is also known as a great circle line if based on a sphere rather than an ellipsoid.
- GREAT_ELLIPTIC—The line on a spheroid (ellipsoid) defined by the intersection at the surface by a plane that passes through the center of the spheroid and the start and endpoints of a segment. This is also known as a great circle when a sphere is used.
- LOXODROME—The line follows a single compass bearing, or azimuth. Great circle routes are often broken into a series of loxodromes, which simplifies navigation. This is also known as a rhumb line.
- PLANAR—Planar measurements use 2D Cartesian mathematics to calculate lengths and areas. This option is only available when measuring in a projected coordinate system and the 2D plane of that coordinate system will be used as the basis for the measurements. Planar measurements reflect the projection of geographic data onto a 2D surface, and do not account for the curvature of the earth.
- PRESERVE_SHAPE—This type calculates the area or length of the geometry on the surface of the earth ellipsoid, for geometry defined in a projected or geographic coordinate system. This option preserves the shape of the geometry in its coordinate system.
(The default value is GEODESIC) | String |

units | The units in which the area will be calculated. - SquareKilometers—Square kilometers
- Hectares—Hectares
- Ares—Ares
- SquareMeters—Square meters
- SquareDecimeters—Square decimeters
- SquareCentimeters—Square centimeters
- SquareMillimeters—Square millimeters
- SquareMiles—Square miles
- AcresInt—International acres
- SquareYardsInt—Square international yards
- SquareFeetInt—Square international feet
- SquareInchesInt—Square international inches
- SquareMilesUS—Square US survey miles
- AcresUS—Square US survey acres
- SquareYardsUS—Square US survey yards
- SquareFeetUS—Square US survey feet
- SquareInchesUS—Square US survey inches
- Unknown—Unknown
| String |

Data Type | Explanation |

Double | The area of the feature. By default, for projected coordinate systems, area will be returned in the units of the coordinate system, and for geographic coordinate systems, area will be returned in square meters. |

getLength ({measurement_type}, {units})

Parameter | Explanation | Data Type |

measurement_type | The method used to measure length. - GEODESIC—The shortest line between any two points on the earth's surface on a spheroid (ellipsoid). One use for a geodesic line is to determine the shortest distance between two cities for an airplane's flight path. This is also known as a great circle line if based on a sphere rather than an ellipsoid.
- GREAT_ELLIPTIC—The line on a spheroid (ellipsoid) defined by the intersection at the surface by a plane that passes through the center of the spheroid and the start and endpoints of a segment. This is also known as a great circle when a sphere is used.
- LOXODROME—The line follows a single compass bearing, or azimuth. Great circle routes are often broken into a series of loxodromes, which simplifies navigation. This is also known as a rhumb line.
- PLANAR—Planar measurements use 2D Cartesian mathematics to calculate lengths and areas. This option is only available when measuring in a projected coordinate system and the 2D plane of that coordinate system will be used as the basis for the measurements. Planar measurements reflect the projection of geographic data onto a 2D surface, and do not account for the curvature of the earth.
- PRESERVE_SHAPE—This type calculates the area or length of the geometry on the surface of the earth ellipsoid, for geometry defined in a projected or geographic coordinate system. This option preserves the shape of the geometry in its coordinate system.
(The default value is GEODESIC) | String |

units | The units in which the length will be calculated. - Kilometers—Kilometers
- Meters—Meters
- Decimeters—Decimeters
- Millimeters—Millimeters
- Centimeters—Centimeters
- NauticalMilesInt—International nautical miles
- MilesInt—Statute miles
- YardsInt—International yards
- FeetInt—International feet
- InchesInt—International inches
- NauticalMiles—US survey nautical miles
- Miles—US survey miles
- Yards—US survey yards
- Feet—US survey feet
- Inches—US survey inches
- DecimalDegrees—Decimal degrees
- Points—Points
- Unknown—Unknown
| String |

Data Type | Explanation |

Double | The length of the feature. By default, for projected coordinate systems, length will be returned in the units of the coordinate system, and for geographic coordinate systems, length will be returned in square meters. |

getPart ({index})

Parameter | Explanation | Data Type |

index | The index position of the geometry. | Integer |

Data Type | Explanation |

Array | The resultant Array object. |

intersect (other, dimension)

Parameter | Explanation | Data Type |

other | The second geometry. | Object |

dimension | The topological dimension (shape type) of the resulting geometry. - 1—A zero-dimensional geometry (point or multipoint).
- 2—A one-dimensional geometry (polyline).
- 4—A two-dimensional geometry (polygon).
| Integer |

Data Type | Explanation |

Object | A new geometry (point, multipoint, polyline, or polygon) that is the geometric intersection of the two input geometries. |

overlaps (second_geometry)

Parameter | Explanation | Data Type |

second_geometry | A second geometry. | Object |

Data Type | Explanation |

Boolean | A return Boolean value of True indicates the intersection of the two geometries has the same dimension as one of the input geometries. |

pointFromAngleAndDistance (angle, distance, {method})

Parameter | Explanation | Data Type |

angle | The angle in degrees to the returned point. | Double |

distance | The distance in the units of the geometry's spatial reference to the returned point. | Double |

method | PLANAR measurements reflect the projection of geographic data onto the 2D surface (in other words, they will not take into account the curvature of the earth). GEODESIC, GREAT_ELLIPTIC, LOXODROME, or PRESERVE_SHAPE measurement types can be chosen as an alternative if desired. - GEODESIC—The shortest line between any two points on the earth's surface on a spheroid (ellipsoid). One use for a geodesic line is when you want to determine the shortest distance between two cities for an airplane's flight path. This is also known as a great circle line if based on a sphere rather than an ellipsoid.
- LOXODROME—A loxodrome is not the shortest distance between two points but instead defines the line of constant bearing, or azimuth. Great circle routes are often broken into a series of loxodromes, which simplifies navigation. This is also known as a rhumb line.
- PLANAR—Planar measurements use 2D Cartesian mathematics to calculate lengths and areas. This option is only available when measuring in a projected coordinate system, and the 2D plane of that coordinate system will be used as the basis for the measurements.
- PRESERVE_SHAPE—This type calculates the area or length of the geometry on the surface of the earth ellipsoid for geometry defined in a projected or geographic coordinate system. This option preserves the shape of the geometry in its coordinate system.
(The default value is GEODESIC) | String |

Data Type | Explanation |

PointGeometry | Returns a point at a given angle and distance in degrees and meters. |

positionAlongLine (value, {use_percentage}, {geodesic})

Parameter | Explanation | Data Type |

value | The distance along the line. If the distance is less than zero, the starting point of the line will be returned; if the distance is greater than the length of the line, the endpoint of the line will be returned. | Double |

use_percentage | Specifies whether the distance is specified as a fixed unit of measure or a ratio of the length of the line. If True, value is used as a percentage; if False, value is used as a distance. For percentages, the value should be expressed as a double from 0.0 (0 percent) to 1.0 (100 percent). (The default value is False) | Boolean |

geodesic | Specifies whether the distance measure is geodesic or planar. If True, the distance measure is treated as geodesic; if False, the distance measure is treated as planar. (The default value is False) | Boolean |

Data Type | Explanation |

PointGeometry | The point on the line at a specified distance from the beginning of the line. |

projectAs (spatial_reference, {transformation_name})

Parameter | Explanation | Data Type |

spatial_reference | The new spatial reference. This can be a SpatialReference object or the coordinate system name. | SpatialReference |

transformation_name | The geotransformation name. | String |

Data Type | Explanation |

Object | The projected geometry. |

symmetricDifference (other)

Parameter | Explanation | Data Type |

other | A second geometry. | Object |

Data Type | Explanation |

Object | The resulting geometry. |

touches (second_geometry)

Parameter | Explanation | Data Type |

second_geometry | A second geometry. | Object |

Data Type | Explanation |

Boolean | A return Boolean value of True indicates the boundaries of the geometries intersect. |

union (other)

Parameter | Explanation | Data Type |

other | A second geometry. | Object |

Data Type | Explanation |

Object | The resulting geometry. |

within (second_geometry, {relation})

Parameter | Explanation | Data Type |

second_geometry | A second geometry. | Object |

relation | The spatial relationship type. - BOUNDARY— Relationship has no restrictions for interiors or boundaries.
- CLEMENTINI— Interiors of geometries must intersect. Specifying CLEMENTINI is equivalent to specifying None. This is the default.
- PROPER— Boundaries of geometries must not intersect.
(The default value is None) | String |

Data Type | Explanation |

Boolean | A return Boolean value of True indicates this geometry is contained within the second geometry. |

## Code sample

Create a polygon feature class from scratch.

```
import arcpy
# A list of features and coordinate pairs
feature_info = [[[1, 2], [2, 4], [3, 7]],
[[6, 8], [5, 7], [7, 2], [9, 5]]]
# A list that will hold each of the Polygon objects
features = []
# Create Polygon objects based an the array of points
for feature in feature_info:
array = arcpy.Array([arcpy.Point(*coords) for coords in feature])
# Add the first coordinate pair to the end to close polygon
array.append(array[0])
features.append(arcpy.Polygon(array))
# Persist a copy of the geometry objects using CopyFeatures
arcpy.CopyFeatures_management(features, "c:/geometry/polygons.shp")
```