SpatialReference (arcpy)

摘要

空间参考的每一部分都具有多个属性，特别是坐标系，它定义了哪些地图投影选项用于定义水平坐标。

讨论

也可使用 Describe spatialReference 属性从现有数据集访问 SpatialReference 对象。

dataset = "c:/data/landbase.gdb/Wetlands"
spatial_ref = arcpy.Describe(dataset).spatialReference
注注:

空间参考属性的可用性取决于所使用的坐标系。在下面的属性列表中，只可用于投影坐标系的属性以 1 表示；只可用于地理坐标系的属性以 2 表示。

语法

SpatialReference ({item})
参数说明数据类型
item

The spatial reference can be created in three ways:

  • Using the name of the coordinate system
    sr = arcpy.SpatialReference("Hawaii Albers Equal Area Conic")
  • Using a projection file (.prj)
    sr = arcpy.SpatialReference("c:/coordsystems/NAD 1983.prj")
  • Using a coordinate system's factory code (or authority code)
    # 32145 is the code for: 
#  NAD 1983 StatePlane Vermont FIPS 4400 (Meters)
sr = arcpy.SpatialReference(32145)

For more information on coordinate system names and factory codes, see geographic_coordinate_systems.pdf and projected_coordinate_systems.pdf files in the ArcGIS Documentation folder.

For more information, see Using the spatial reference class.

String

属性

属性说明数据类型
GCS
(只读)

If a projected coordinate system, returns a SpatialReference object for the geographic coordinate system it is based on. If a geographic coordinate system, returns the same SpatialReference.

SpatialReference
MDomain
(只读)

The extent of the measure domain.

String
MFalseOriginAndUnits
(只读)

The measure false origin and units.

String
MResolution
(读写)

The measure resolution.

Double
MTolerance
(读写)

The measure tolerance.

Double
XYResolution
(读写)

The xy resolution.

Double
XYTolerance
(读写)

The xy tolerance.

Double
ZDomain
(只读)

The extent of the Z domain.

String
ZFalseOriginAndUnits
(只读)

The Z false origin and units.

String
ZResolution
(读写)

The Z resolution property.

Double
ZTolerance
(读写)

The Z tolerance property.

Double
abbreviation
(读写)

The abbreviated name of the spatial reference.

String
alias
(读写)

The alias of the spatial reference.

String
domain
(只读)

The extent of the xy domain.

String
factoryCode
(读写)

The factory code of the spatial reference.

Integer
falseOriginAndUnits
(只读)

The false origin and units.

String
hasMPrecision
(只读)

Indicates whether or not m-value precision information has been defined.

Boolean
hasXYPrecision
(只读)

Indicates whether or not xy precision information has been defined.

Boolean
hasZPrecision
(只读)

Indicates whether or not z-value precision information has been defined.

Boolean
isHighPrecision
(读写)

Indicates whether or not the spatial reference has high precision set.

Boolean
name
(读写)

The name of the spatial reference.

String
remarks
(读写)

The comment string of the spatial reference.

String
type
(读写)

The type of the spatial reference.

String
usage
(只读)

The usage notes.

String
PCSCode
(读写)

投影坐标系代码。1

Integer
PCSName
(读写)

投影坐标系名称。1

String
azimuth
(读写)

投影坐标系的方位角。1

Double
centralMeridian
(读写)

投影坐标系的中央经线。1

Double
centralMeridianInDegrees
(读写)

投影坐标系的中央经线 (Lambda0)（以度为单位）。1

Double
centralParallel
(读写)

投影坐标系的中央纬线。1

Double
classification
(只读)

地图投影的分类。1

String
falseEasting
(读写)

投影坐标系的东偏移量。1

Double
falseNorthing
(读写)

投影坐标系的北偏移量。1

Double
latitudeOf1st
(读写)

投影坐标系第一个点的纬度。1

Double
latitudeOf2nd
(读写)

投影坐标系第二个点的纬度。1

Double
linearUnitCode
(读写)

线性单位代码。1

Integer
linearUnitName
(读写)

线性单位名称。1

String
longitude
(读写)

此本初子午线的经度值。1

Double
longitudeOf1st
(读写)

投影坐标系第一个点的经度。1

Double
longitudeOf2nd
(读写)

投影坐标系第二个点的经度。1

Double
longitudeOfOrigin
(读写)

投影坐标系原点的经度。1

Double
metersPerUnit
(只读)

米/线性单位。1

Double
projectionCode
(读写)

投影代码。1

Integer
projectionName
(读写)

投影名称。1

String
scaleFactor
(读写)

投影坐标系的比例因子。1

Double
standardParallel1
(读写)

投影坐标系的第一条纬线。1

Double
standardParallel2
(读写)

投影坐标系的第二条纬线。1

Double
GCSCode
(读写)

The geographic coordinate system code.2

Integer
GCSName
(读写)

The geographic coordinate system name.2

String
angularUnitCode
(读写)

The angular unit code.2

Integer
angularUnitName
(读写)

The angular unit name.2

String
datumCode
(读写)

The datum code.2

Integer
datumName
(读写)

The datum name.2

String
flattening
(读写)

The flattening ratio of this spheroid.2

Double
longitude
(读写)

The longitude value of this prime meridian.2

Double
primeMeridianCode
(读写)

The prime meridian code.2

Integer
primeMeridianName
(读写)

The prime meridian name.2

String
radiansPerUnit
(只读)

The radians per angular unit.2

Double
semiMajorAxis
(读写)

The semi-major axis length of this spheroid.2

Double
semiMinorAxis
(读写)

The semi-minor axis length of this spheroid.2

Double
spheroidCode
(读写)

The spheroid code.2

Integer
spheroidName
(读写)

The spheroid name.2

String

方法概述

方法说明
create ()

Creates the spatial reference object using properties.

createFromFile (prj_file)

Creates the spatial reference object from a projection file.

exportToString ()

Exports the object to its string representation.

loadFromString (string)

Restore the object using its string representation. The exportToString method can be used to create a string representation.

setDomain (x_min, x_max, y_min, y_max)

设置 XY 属性域。

setFalseOriginAndUnits (false_x, false_y, xy_units)

Sets the XY false origin and units.

setMDomain (m_min, m_max)

Sets the M domain.

setMFalseOriginAndUnits (false_m, m_units)

设置 M 的假定原点和单位。

setZDomain (z_min, z_max)

Sets the Z domain.

setZFalseOriginAndUnits (false_z, z_units)

设置 Z 的假定原点和单位。

方法

create ()
createFromFile (prj_file)
参数说明数据类型
prj_file

The projection file used to populate the spatial reference object.

String
exportToString ()
返回值
数据类型说明
String

The string representation of the object.

loadFromString (string)
参数说明数据类型
string

The string representation of the object.

String
setDomain (x_min, x_max, y_min, y_max)
参数说明数据类型
x_min

The minimum x-value.

Double
x_max

The maximum x-value.

Double
y_min

The minimum y-value.

Double
y_max

The maximum y-value.

Double
setFalseOriginAndUnits (false_x, false_y, xy_units)
参数说明数据类型
false_x

The false x value.

Double
false_y

The false y value.

Double
xy_units

The xy units.

String
setMDomain (m_min, m_max)
参数说明数据类型
m_min

The minimum m-value.

Double
m_max

The maximum m-value.

Double
setMFalseOriginAndUnits (false_m, m_units)
参数说明数据类型
false_m

The false m-value.

Double
m_units

The m units.

Double
setZDomain (z_min, z_max)
参数说明数据类型
z_min

The minimum z-value.

Double
z_max

The maximum z-value.

Double
setZFalseOriginAndUnits (false_z, z_units)
参数说明数据类型
false_z

The false z-value.

Double
z_units

The false z units.

Double

代码实例

SpatialReference 示例

对工作空间中的每个要素类，输出其空间参考的名称。

import arcpy

# Set the workspace environment
arcpy.env.workspace = "c:/base/base.gdb"

# Get a list of the feature classes in the input folder
feature_classes = arcpy.ListFeatureClasses()

# Loop through the list
for fc in feature_classes:
    # Create the spatial reference object
    spatial_ref = arcpy.Describe(fc).spatialReference

    # If the spatial reference is unknown
    if spatial_ref.name == "Unknown":
        print("{0} has an unknown spatial reference".format(fc))

    # Otherwise, print out the feature class name and
    # spatial reference
    else:
        print("{0} : {1}".format(fc, spatial_ref.name))

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5/10/2014