简介

要素（Feature）是PIE-Engine中的矢量要素对象，对应矢量数据中的一条记录，包括几何图形信息和属性信息。PIE-Engine Studio提供构建要素算子及要素相关算法，包括但不限于获取要素属性信息、几何信息，判断要素间位置关系，要素间空间分析计算。

Feature

函数	返回值
Feature(geometry,properties)	Feature

参数	类型	说明
geometry	Geometry	几何形体对象
properties	Json	属性信息JSON对象

示例

polyline = pie.Geometry.LineString([[118, 31.1],[119, 32.1]], None)
feature = pie.Feature(polyline.bounds(0,None))
Map = pie.Map()
Map.addLayer(feature,{'color':'red'},'feature')
Map.setCenter(118.5,31.6,8)
Map

area

计算矢量图形对象的面积，只对面有效。

函数	返回值
area(self,proj)	Number

参数	类型	说明
proj	Dictionary	设置投影方式

示例

polygon = pie.Geometry.Polygon([[
    [
        76.0641376209303,
        44.11876326018208
    ],
    [
        80.83964695953506,
        49.800143138994855
    ],
    [
        89.95652842415888,
        48.14753031988744
    ],
    [
        82.74985069498081,
        41.50791700751361
    ],
    [
        76.0641376209303,
        44.11876326018208
    ]
]], None)
p_feature = pie.Feature(polygon)
print(p_feature.area(None).getInfo())

buffer

返回矢量要素的几何图形在给定距离生成的缓冲区。

函数	返回值
buffer(self, distance, proj)	Feature

参数	类型	说明
distance	Int	缓冲距离
proj	Dictionary	设置投影方式

示例

polygon = pie.Geometry.Polygon([[
    [
        76.0641376209303,
        44.11876326018208
    ],
    [
        80.83964695953506,
        49.800143138994855
    ],
    [
        89.95652842415888,
        48.14753031988744
    ],
    [
        82.74985069498081,
        41.50791700751361
    ],
    [
        76.0641376209303,
        44.11876326018208
    ]
]], None)
p_feature = pie.Feature(polygon)
p_buffer = p_feature.buffer(100000, None)

Map = pie.Map()
Map.addLayer(p_feature, {'color': 'blue'}, 'p_feature')
Map.addLayer(p_buffer, {'color': 'red'}, 'p_buffer')
Map.setCenter(84,46,5)
Map

containedIn

判断左边矢量要素的Geometry是否包含在右边矢量要素的Geometry中，若包含返回True，不包含返回False。

函数	返回值
containedIn(self,right,proj)	Boolean

参数	类型	说明
right	Feature	矢量对象
proj	Dictionary	设置投影方式

示例

a = pie.Geometry.Polygon([[
    [
        86.80129479936647,
        47.42899226581099
    ],
    [
        82.87305373501061,
        47.53413332597603
    ],
    [
        79.52821480892538,
        44.62131637232005
    ],
    [
        95.12449863869472,
        40.29107652773166
    ],
    [
        96.56355724642901,
        43.390491195479
    ],
    [
        86.80129479936647,
        47.42899226581099
    ]
]], None)
b = pie.Geometry.Polygon([[
    [
        76.0641376209303,
        44.11876326018208
    ],
    [
        80.83964695953506,
        49.800143138994855
    ],
    [
        89.95652842415888,
        48.14753031988744
    ],
    [
        82.74985069498081,
        41.50791700751361
    ],
    [
        76.0641376209303,
        44.11876326018208
    ]
]], None)

af = pie.Feature(a)
bf = pie.Feature(b)
print(af.containedIn(bf, None).getInfo())

contains

判断左边矢量要素的Geometry是否包含右边矢量要素的Geometry，若包含返回True，不包含返回False。

函数	返回值
contains(self,right,proj)	Boolean

参数	类型	说明
right	Feature	矢量对象
proj	Dictionary	设置投影方式

示例

a = pie.Geometry.Polygon([[
    [
        86.80129479936647,
        47.42899226581099
    ],
    [
        82.87305373501061,
        47.53413332597603
    ],
    [
        79.52821480892538,
        44.62131637232005
    ],
    [
        95.12449863869472,
        40.29107652773166
    ],
    [
        96.56355724642901,
        43.390491195479
    ],
    [
        86.80129479936647,
        47.42899226581099
    ]
]], None)
b = pie.Geometry.Polygon([[
    [
        76.0641376209303,
        44.11876326018208
    ],
    [
        80.83964695953506,
        49.800143138994855
    ],
    [
        89.95652842415888,
        48.14753031988744
    ],
    [
        82.74985069498081,
        41.50791700751361
    ],
    [
        76.0641376209303,
        44.11876326018208
    ]
]], None)

af = pie.Feature(a)
bf = pie.Feature(b)
print(af.contains(bf, None).getInfo())

difference

计算左边矢量要素的Geometry和右边矢量要素的Geometry差集。

函数	返回值
difference(self, right, proj)	Boolean

参数	类型	说明
right	Feature	矢量对象
proj	Dictionary	设置投影方式

示例

a = pie.Geometry.Polygon([[
    [
        86.80129479936647,
        47.42899226581099
    ],
    [
        82.87305373501061,
        47.53413332597603
    ],
    [
        79.52821480892538,
        44.62131637232005
    ],
    [
        95.12449863869472,
        40.29107652773166
    ],
    [
        96.56355724642901,
        43.390491195479
    ],
    [
        86.80129479936647,
        47.42899226581099
    ]
]], None)
b = pie.Geometry.Polygon([[
    [
        76.0641376209303,
        44.11876326018208
    ],
    [
        80.83964695953506,
        49.800143138994855
    ],
    [
        89.95652842415888,
        48.14753031988744
    ],
    [
        82.74985069498081,
        41.50791700751361
    ],
    [
        76.0641376209303,
        44.11876326018208
    ]
]], None)

af = pie.Feature(a)
bf = pie.Feature(b)
cf = af.difference(bf, None)
print(cf.geometry().getInfo())

Map = pie.Map()
Map.addLayer(af, {'color': 'red'}, 'af')
Map.addLayer(bf, {'color':'blue'}, 'bf')
Map.addLayer(cf, {'color':'yellow'}, 'cf')
Map.setCenter(84,45,5)
Map

disjoint

判断左边矢量要素的Geometry是否和右边矢量要素的Geometry相离，若相离返回True，不相离返回False。

函数	返回值
disjoint(self,right,proj)	Boolean

参数	类型	说明
right	Feature	矢量对象
proj	Dictionary	设置投影方式

示例

a = pie.Geometry.Polygon([[
    [
        86.80129479936647,
        47.42899226581099
    ],
    [
        82.87305373501061,
        47.53413332597603
    ],
    [
        79.52821480892538,
        44.62131637232005
    ],
    [
        95.12449863869472,
        40.29107652773166
    ],
    [
        96.56355724642901,
        43.390491195479
    ],
    [
        86.80129479936647,
        47.42899226581099
    ]
]], None)
b = pie.Geometry.Polygon([[
    [
        76.0641376209303,
        44.11876326018208
    ],
    [
        80.83964695953506,
        49.800143138994855
    ],
    [
        89.95652842415888,
        48.14753031988744
    ],
    [
        82.74985069498081,
        41.50791700751361
    ],
    [
        76.0641376209303,
        44.11876326018208
    ]
]], None)

af = pie.Feature(a)
bf = pie.Feature(b)
print(af.disjoint(bf, None).getInfo())

geometry

获得矢量要素的几何形体。

函数	返回值
geometry(maxError,proj,geodesic)	Geometry

参数	类型	说明
maxError	MaxError	未启用
proj	Project	坐标系，默认为WGS84
geodesic	Boolean	未启用

示例

featureCollection = pie.FeatureCollection("NGCC/CHINA_PROVINCE_BOUNDARY")
f0 = featureCollection.getAt(0).geometry()
print(f0.getInfo())

get

根据属性名获得Feature下该属性值信息。

函数	返回值
get(self,key)	Value

参数	类型	说明
key	String	属性名

示例

geometry = pie.Geometry.LineString([
    [
        116.47239746093555,
        39.90895451343508
    ],
    [
        115.61247314452947,
        40.701053532910964
    ]
], None)
f = pie.Feature(geometry)
f = f.set("key1",1)
value = f.get("key1")
print(value.getInfo())

getArray

根据属性名获得Feature下的属性值信息，并且将其转换为数组类型。

函数	返回值
getArray(property)	Array

参数	类型	说明
property	String	属性名

示例

featureCollection = pie.FeatureCollection("user/101/public/shape/Shi_HeBei")
value = featureCollection.first().getArray("Bianma").getInfo()
print(value)

getNumber

根据属性名获得Feature下的属性值信息，并且将其转换为数值类型。

函数	返回值
getNumber(property)	Number

参数	类型	说明
property	String	属性名

示例

featureCollection = pie.FeatureCollection("user/101/public/shape/Shi_HeBei")
value = featureCollection.first().getNumber("Bianma").getInfo()
print(value)

getString

根据属性名获得Feature下的属性值信息，并且将其转换为字符串类型。

函数	返回值
getString(property)	String

参数	类型	说明
property	String	属性名

示例

featureCollection = pie.FeatureCollection("user/101/public/shape/Shi_HeBei")
value = featureCollection.first().getString("NAME").getInfo()
print(value)

id

返回Feature对象的id。

函数	返回值
id()	String

示例

featureCollection = pie.FeatureCollection("user/101/public/shape/Shi_HeBei")
feature = featureCollection.first()
id = feature.id().getInfo()
print(id)

intersection

计算左边矢量要素的Geometry和右边矢量要素的Geometry交集。

函数	返回值
intersection(self, right, proj)	Feature

参数	类型	说明
right	Feature	矢量对象
proj	Dictionary	设置投影方式

示例

a = pie.Geometry.Polygon([[
    [
        86.80129479936647,
        47.42899226581099
    ],
    [
        82.87305373501061,
        47.53413332597603
    ],
    [
        79.52821480892538,
        44.62131637232005
    ],
    [
        95.12449863869472,
        40.29107652773166
    ],
    [
        96.56355724642901,
        43.390491195479
    ],
    [
        86.80129479936647,
        47.42899226581099
    ]
]], None)
b = pie.Geometry.Polygon([[
    [
        76.0641376209303,
        44.11876326018208
    ],
    [
        80.83964695953506,
        49.800143138994855
    ],
    [
        89.95652842415888,
        48.14753031988744
    ],
    [
        82.74985069498081,
        41.50791700751361
    ],
    [
        76.0641376209303,
        44.11876326018208
    ]
]], None)

af = pie.Feature(a)
bf = pie.Feature(b)
cf = af.intersection(bf, None)
print(cf.geometry().getInfo())

Map = pie.Map()
Map.addLayer(af, {'color': 'red'}, 'af')
Map.addLayer(bf, {'color': 'blue'}, 'bf')
Map.addLayer(cf, {'color': 'yellow'}, 'cf')
Map.setCenter(84,46,5)
Map

intersects

判断左边矢量要素的Geometry是否和右边矢量要素的Geometry相交，若相交返回True，不相交返回False。

函数	返回值
intersects(self,right,proj)	Boolean

参数	类型	说明
right	Feature	矢量对象
proj	Dictionary	设置投影方式

示例

a = pie.Geometry.Polygon([[
    [
        86.80129479936647,
        47.42899226581099
    ],
    [
        82.87305373501061,
        47.53413332597603
    ],
    [
        79.52821480892538,
        44.62131637232005
    ],
    [
        95.12449863869472,
        40.29107652773166
    ],
    [
        96.56355724642901,
        43.390491195479
    ],
    [
        86.80129479936647,
        47.42899226581099
    ]
]], None)
b = pie.Geometry.Polygon([[
    [
        76.0641376209303,
        44.11876326018208
    ],
    [
        80.83964695953506,
        49.800143138994855
    ],
    [
        89.95652842415888,
        48.14753031988744
    ],
    [
        82.74985069498081,
        41.50791700751361
    ],
    [
        76.0641376209303,
        44.11876326018208
    ]
]], None)

af = pie.Feature(a)
bf = pie.Feature(b)
print(af.intersects(bf, None).getInfo())

length

计算矢量图形对象的长度或周长，只对线面有效。

函数	返回值
length(self,proj)	Number

参数	类型	说明
proj	Dictionary	设置投影方式

示例

line = pie.Geometry.LineString([
    [
        86.21755088013333,
        42.173683155554215
    ],
    [
        95.75003820467464,
        45.90600966211181
    ], 
],None)
l_feature = pie.Feature(line)
print(l_feature.length(None).getInfo())

propertyNames

返回Feature对象的属性名列表。

函数	返回值
propertyNames()	List

示例

featureCollection = pie.FeatureCollection("user/101/public/shape/Shi_HeBei")
feature = featureCollection.first()
feature = feature.set("key1", 123)
propertyNames = feature.propertyNames().getInfo()
print(propertyNames)

set

设置Feature下的指定属性的属性值，如果存在就覆盖更新，如果不存在则直接创建。

函数	返回值
Set(self,key,value)	Void

参数	类型	说明
key	String	属性名
value	String|Number|Boolean|Object|List	属性值

示例

geometry = pie.Geometry.LineString([  
    [  
        116.47239746093555,  
        39.90895451343508  
    ],  
    [  
        115.61247314452947,  
        40.701053532910964  
    ]  
], None)  
f = pie.Feature(geometry)  
f_set = f.set("key1", [1,2,3])  
f_set2 = f.set('properties', 'feature')
print(f_set.getInfo())  
print(f_set2.getInfo())

setGeometry

设置矢量要素的几何形体对象。

函数	返回值
setGeometry(geometry)	Feature

参数	类型	说明
geometry	Geometry	几何形体对象

示例

polyline = pie.Geometry.LineString([[118, 31.1],[119, 32.1]], None)
feature = pie.Feature().setGeometry(polyline.bounds(0,None))

Map = pie.Map()
Map.addLayer(feature,{'color':'red'},'feature')
Map.addLayer(pie.Feature(polyline),{'color':'blue'},'polyline')
Map.setCenter(118.5,31.5,8)
Map

setMulti

批量设置Feature下的属性信息，如果存在就覆盖更新，如果不存在则直接创建。

函数	返回值
setMulti(properties)	Void

参数	类型	说明
properties	Dictionary	属性键值对，以字典形式传入

示例

featureCollection = pie.FeatureCollection("user/101/public/shape/Shi_HeBei")
feature = featureCollection.first()
dict = {'key1': "123", 'key2': 12.34, 'key3': [1, 2, 3, 4, 5, 6]}
feature = feature.setMulti(dict)
print(feature.getInfo())

simplify

简化矢量图形对象。

函数	返回值
simplify(self,proj)	Feature

参数	类型	说明
proj	Dictionary	设置投影方式

示例

featureCollection = pie.FeatureCollection("NGCC/CHINA_PROVINCE_BOUNDARY")
f0 = featureCollection.getAt(0)
print(f0.simplify(None).getInfo())

union

计算左边矢量要素的Geometry和右边矢量要素的Geometry并集。

函数	返回值
union(self, right, proj)	Feature

参数	类型	说明
right	Feature	矢量对象
proj	Dictionary	设置投影方式

示例

a = pie.Geometry.Polygon([[
    [
        86.80129479936647,
        47.42899226581099
    ],
    [
        82.87305373501061,
        47.53413332597603
    ],
    [
        79.52821480892538,
        44.62131637232005
    ],
    [
        95.12449863869472,
        40.29107652773166
    ],
    [
        96.56355724642901,
        43.390491195479
    ],
    [
        86.80129479936647,
        47.42899226581099
    ]
]], None)
b = pie.Geometry.Polygon([[
    [
        76.0641376209303,
        44.11876326018208
    ],
    [
        80.83964695953506,
        49.800143138994855
    ],
    [
        89.95652842415888,
        48.14753031988744
    ],
    [
        82.74985069498081,
        41.50791700751361
    ],
    [
        76.0641376209303,
        44.11876326018208
    ]
]], None)

af = pie.Feature(a)
bf = pie.Feature(b)
cf = af.union(bf, None)
print(cf.geometry().getInfo())

Map = pie.Map()
Map.addLayer(af, {'color': 'red'}, 'af')
Map.addLayer(bf, {'color': 'blue'}, 'bf')
Map.addLayer(cf, {'color': 'yellow'}, 'cf')
Map.setCenter(84,46,5)
Map

withinDistance

判断左边矢量要素的Geometry与右边矢量要素的Geometry相隔距离是否在给定的范围内，若是返回Ttrue，不是返回False。

函数	返回值
withinDistance(self,right,distance,proj)	Boolean

参数	类型	说明
right	Feature	矢量对象
proj	Dictionary	设置投影方式
distance	int	缓冲距离

示例

featureCollection = pie.FeatureCollection("NGCC/CHINA_PROVINCE_BOUNDARY")
f0 = featureCollection.getAt(0)
f1 = featureCollection.getAt(1)
print(f0.withinDistance(f1,1000000,None).getInf