Résumé
A PointGeometry is a shape that has neither length nor area at a given scale.
Discussion
Dans de nombreux workflows de géotraitement, vous devez éventuellement exécuter une opération spécifique à l'aide d'informations sur les coordonnées et la géométrie, sans vouloir nécessairement créer une nouvelle classe d'entités (temporaire), la remplir avec des curseurs, l'utiliser, puis la supprimer. Les objets géométrie peuvent alors être utilisés en entrée et en sortie afin de simplifier le géotraitement. Les objets géométrie peuvent être entièrement créés à l'aide des classes Geometry, Multipoint, PointGeometry, Polygon ou Polyline.
Syntaxe
PointGeometry (inputs, {spatial_reference}, {has_z}, {has_m})
Paramètre | Explication | Type de données |
inputs | The Point used to create the object. | Point |
spatial_reference | The spatial reference of the new geometry. (La valeur par défaut est None) | SpatialReference |
has_z | The Z state: True for geometry if Z is enabled and False if it is not. (La valeur par défaut est False) | Boolean |
has_m | The M state: True for geometry if M is enabled and False if it is not. (La valeur par défaut est False) | Boolean |
Propriétés
Propriété | Explication | Type de données |
JSON (Lecture seule) | Returns an Esri JSON representation of the geometry as a string. Astuce :The returned string can be converted to a dictionary using the Python json.loads function. | String |
WKB (Lecture seule) | 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 (Lecture seule) | 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 (Lecture seule) | The area of a polygon feature. It is zero for all other feature types. | Double |
centroid (Lecture seule) | The true centroid if it is within or on the feature; otherwise, the label point is returned. | Point |
extent (Lecture/écriture) | The extent of the geometry. | Extent |
firstPoint (Lecture seule) | The first coordinate point of the geometry. | Point |
hasCurves (Lecture seule) | Returns True if the geometry has a curve. | Boolean |
hullRectangle (Lecture seule) | A space-delimited string of the coordinate pairs of the convex hull rectangle. | String |
isMultipart (Lecture seule) | Returns True if the number of parts for this geometry is more than one. | Boolean |
labelPoint (Lecture seule) | The point at which the label is located. The labelPoint is always located within or on a feature. | Point |
lastPoint (Lecture seule) | The last coordinate of the feature. | Point |
length (Lecture seule) | The length of the linear feature. It is zero for point and multipoint feature types. | Double |
length3D (Lecture/écriture) | The 3D length of the linear feature. It is zero for point and multipoint feature types. | Double |
partCount (Lecture seule) | The number of geometry parts for the feature. | Integer |
pointCount (Lecture seule) | The total number of points for the feature. | Integer |
spatialReference (Lecture seule) | The spatial reference of the geometry. | SpatialReference |
trueCentroid (Lecture seule) | The center of gravity for a feature. | Point |
type (Lecture seule) | The geometry type: polygon, polyline, point, multipoint, multipatch, dimension, or annotation. | String |
Vue d’ensemble des méthodes
Méthode | Explication |
angleAndDistanceTo (other, {method}) | Returns a tuple of angle and distance to another point using a measurement type. |
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) | Indique si les deux géométries s'intersectent dans une géométrie de type de forme inférieure. Deux polylignes se croisent si elles partagent uniquement des points, dont au moins un n'est pas une extrémité. Une polyligne et un polygone se croisent s'ils partagent une polyligne ou un point (pour une ligne verticale) à l'intérieur du polygone qui n'est pas équivalent à la polyligne entière. Only True relationships are shown in this illustration. |
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) | Indique si la géométrie de base et la géométrie de comparaison n'ont aucun point en commun. Deux géométries s'intersectent si la propriété disjoint renvoie False. Only True relationships are shown in this illustration. |
distanceTo (other) | Returns the minimum distance between two geometries. 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. |
getGeohash (precision) | Converts a PointGeometry in geographic coordinate system coordinates of latitude and longitude to a geohash string that is accurate to an arbitrary precision within a bounding box in the geohash grid. |
getPart ({index}) | Returns an array of point objects for a particular part of geometry or an array containing a number of arrays, one for each part. 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) | Indique si l'intersection des deux géométries possède le même type de forme que l'une des géométries en entrée et qu'elle n'est pas équivalente à l'une des géométries en entrée. 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. |
projectAs (spatial_reference, {transformation_name}) | Projects a geometry and optionally applies a geotransformation. To project, the geometry needs to have a spatial reference, and not have an UnknownCoordinateSystem. 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 measure 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. |
toCoordString (notation) | Converts a PointGeometry to the selected coordinate system notation. |
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. |
Méthodes
angleAndDistanceTo (other, {method})
Paramètre | Explication | Type de données |
other | The second geometry. | PointGeometry |
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, and PRESERVE_SHAPE measurement types may be chosen as an alternative, if desired.
(La valeur par défaut est GEODESIC) | String |
Type de données | Explication |
tuple | Returns a tuple of angle (in degrees) and distance (in meters) to another point. |
boundary ()
Type de données | Explication |
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)
Paramètre | Explication | Type de données |
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 |
Type de données | Explication |
Polygon | The buffered polygon geometry. |
clip (envelope)
Paramètre | Explication | Type de données |
envelope | An extent object used to define the clip extent. | Extent |
Type de données | Explication |
Object | An output geometry clipped to the specified extent. |
contains (second_geometry, {relation})
Paramètre | Explication | Type de données |
second_geometry | A second geometry. | Object |
relation | The spatial relationship type.
(La valeur par défaut est None) | String |
Type de données | Explication |
Boolean |
A return Boolean value of True indicates this geometry contains the second geometry. |
convexHull ()
Type de données | Explication |
Object | The resulting geometry. The convex hull of a single point is the point itself. |
crosses (second_geometry)
Paramètre | Explication | Type de données |
second_geometry | A second geometry. | Object |
Type de données | Explication |
Boolean | Une valeur booléenne renvoyée True indique que les deux géométries s'intersectent dans une géométrie de type de forme inférieure. |
difference (other)
Paramètre | Explication | Type de données |
other | A second geometry. | Object |
Type de données | Explication |
Object | The resulting geometry. |
disjoint (second_geometry)
Paramètre | Explication | Type de données |
second_geometry | A second geometry. | Object |
Type de données | Explication |
Boolean | Une valeur booléenne renvoyée True indique que les deux géométries n'ont aucun point en commun. |
distanceTo (other)
Paramètre | Explication | Type de données |
other | A second geometry. | Object |
Type de données | Explication |
Double | The distance between the two geometries. |
equals (second_geometry)
Paramètre | Explication | Type de données |
second_geometry | A second geometry. | Object |
Type de données | Explication |
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. |
getGeohash (precision)
Paramètre | Explication | Type de données |
precision | The precision length of the hash string to return for the PointGeometry. The minimum length is 1 and the maximum length is 20. The default length is 8. (La valeur par défaut est 8) | Integer |
Type de données | Explication |
String | getGeohash returns a geohash string based on the input point geometry latitude and longitude coordinates and the length of precision. |
The spatial reference of the point geometry must be in a geographic coordinate system to return an accurate geohash.
import arcpy
# Spatial reference set to GCS_WGS_1984
spatial_reference = arcpy.SpatialReference(4326)
pnt = arcpy.Point(-88.236, 40.096)
pnt_geometry = arcpy.PointGeometry(pnt, spatial_reference)
print(pnt_geometry.getGeohash(6)) # dp1k05
getPart ({index})
Paramètre | Explication | Type de données |
index | The index position of the geometry. | Integer |
Type de données | Explication |
Array | getPart returns an array of point objects for a particular part of the geometry if an index is specified. If an index is not specified, an array containing an array of point objects for each geometry part is returned. |
intersect (other, dimension)
Paramètre | Explication | Type de données |
other | The second geometry. | Object |
dimension | The topological dimension (shape type) of the resulting geometry.
| Integer |
Type de données | Explication |
Object | A new geometry (point, multipoint, polyline, or polygon) that is the geometric intersection of the two input geometries. |
overlaps (second_geometry)
Paramètre | Explication | Type de données |
second_geometry | A second geometry. | Object |
Type de données | Explication |
Boolean | Une valeur booléenne renvoyée True indique que l'intersection des deux géométries a la même dimension que l'une des géométries en entrée. |
pointFromAngleAndDistance (angle, distance, {method})
Paramètre | Explication | Type de données |
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.
(La valeur par défaut est GEODESIC) | String |
Type de données | Explication |
PointGeometry | Returns a point at a given angle and distance in degrees and meters. |
projectAs (spatial_reference, {transformation_name})
Paramètre | Explication | Type de données |
spatial_reference | The new spatial reference. This can be a SpatialReference object or the coordinate system name. | SpatialReference |
transformation_name | The geotransformation name. | String |
Type de données | Explication |
Object | The projected geometry. |
symmetricDifference (other)
Paramètre | Explication | Type de données |
other | A second geometry. | Object |
Type de données | Explication |
Object | The resulting geometry. |
toCoordString (notation)
Paramètre | Explication | Type de données |
notation | The coordinate system notation to be generated.
| None |
Type de données | Explication |
String | The point in the chosen coordinate system notation. |
touches (second_geometry)
Paramètre | Explication | Type de données |
second_geometry | A second geometry. | Object |
Type de données | Explication |
Boolean | A return Boolean value of True indicates the boundaries of the geometries intersect. |
union (other)
Paramètre | Explication | Type de données |
other | A second geometry. | Object |
Type de données | Explication |
Object | The resulting geometry. |
within (second_geometry, {relation})
Paramètre | Explication | Type de données |
second_geometry | A second geometry. | Object |
relation | The spatial relationship type.
(La valeur par défaut est None) | String |
Type de données | Explication |
Boolean | A return Boolean value of True indicates this geometry is contained within the second geometry. |
Exemple de code
Create a point feature class from scratch.
import arcpy
# A list of coordinate pairs
#
pointList = [[1,2],[3,5],[7,3]]
# Create an empty Point object
#
point = arcpy.Point()
# A list to hold the PointGeometry objects
#
pointGeometryList = []
# For each coordinate pair, populate the Point object and create
# a new PointGeometry
for pt in pointList:
point.X = pt[0]
point.Y = pt[1]
pointGeometry = arcpy.PointGeometry(point)
pointGeometryList.append(pointGeometry)
# Create a copy of the PointGeometry objects, by using pointGeometryList
# as input to the CopyFeatures tool.
#
arcpy.CopyFeatures_management(pointGeometryList, "c:/geometry/a.gdb/points")
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