Summary
Projects spatial data from one coordinate system to another.
Usage
If the input feature class or dataset has an unknown or unspecified coordinate system, you can specify the input dataset's coordinate system with the Input Coordinate System parameter. This allows you to specify the data's coordinate system without having to modify the input data (which may not be possible if the input is a read-only format). Also, you can use the Define Projection tool to permanently assign a coordinate system to the dataset.
All types of feature classes (geodatabase feature classes, coverage feature classes, SDC feature classes, and shapefiles), feature datasets in a geodatabase and feature layers in ArcGIS applications (ArcMap, ArcScene, and ArcGlobe) are valid input.
Coverages, VPF Coverages, raster datasets, and raster catalogs are not supported as input to this tool. Use the Project Raster tool to project raster datasets.
To project a Coverage, use the Project tool in the Coverage toolbox.
The tool's Geographic Transformation parameter is optional. When no geographic or datum transformation is required, no drop-down list will appear on the parameter and it is left blank. When a transformation is required, a drop-down list will be generated based on the input and output datums, and a default transformation will be picked.
- For example, a geographic transformation is not required when projecting from GCS_North_American_1983 to NAD_1983_UTM_Zone_12N because both the input and output coordinate systems have a NAD_1983 datum. However, projecting from GCS_North_American_1983 to WGS_1984_UTM_Zone_12N requires a geographic transformation because the input coordinate system uses the NAD_1983 datum, while the output coordinate system uses the WGS_1984 datum.
- For a list of transformations and their area of use, see the following knowledge base article: 21327 (Esri Knowledge base article #21327).
The in_memory workspace is not supported as a location to write the output dataset.
When projecting the complex data types listed below, certain operations need to be performed on the resulting data:
- Feature dataset containing a network dataset: the network dataset must be rebuilt.
- Feature dataset containing a topology: the topology should be revalidated.
If the input participates in relationship classes (as with feature-linked annotation), the relationship class will be transferred to the output. The exception to this rule relates to participating stand-alone tables.
Depending on the input feature's coordinates and the horizon (valid extent) of the output coordinate system, multipoint, line, and polygon may be clipped or split into more than one part when projecting them. Features that fall completely outside the horizon will be written to the output with a Null shape. These can be deleted using the Repair Geometry tool.
Feature classes participating in a geometric network cannot be projected independently—the entire feature dataset containing the network needs to be projected.
Many geoprocessing tools honor the output coordinate system environment setting, and in many workflows you can use this environment setting instead of using the Project tool. For example, the Union tool honors the output coordinate system environment setting, which means you can union several feature classes together, all of which are in a different coordinate system, and write the unioned output to a feature class in an entirely different coordinate system.
Selection and definition query on layers are ignored by this tool—all features in the dataset referenced by the layer will be projected. If you want to project selected features only, consider using the Copy Features tool to create a temporary dataset, which will only contain the selected features, and use this intermediate dataset as input to the Project tool.
When a feature class within a feature dataset is used as input, the output cannot be written to the same feature dataset. This is because feature classes within a feature dataset must all have the same coordinate system. In this case, the output feature class will be written to the geodatabase containing the feature dataset.
The Preserve Shape parameter, when checked, creates output features that more accurately represent their true projected location. Preserve Shape is especially useful in cases where a line or polygon boundary is digitized as a long, straight line with few vertices. If Preserve Shape is not checked, the existing vertices of the input line or polygon boundary are projected, and the result may be a feature that is not accurately located in the new projection. When Preserve Shape is checked (preserve_shape = "PRESERVE_SHAPE" in Python), extra vertices are added to the feature before projecting. These extra vertices preserve the projected shape of the feature. The Maximum Offset Deviation parameter controls how many extra vertices are added; its value is the maximum distance the projected feature can be offset from its exact projected location as computed by the tool. When the value is small, more vertices are added. Choose a value that suits your needs. For example, if your projected output is for general small-scale cartographic display, a large deviation may be acceptable. If your projected output is to be used in large-scale, small-area analysis, a smaller deviation may be needed.
Syntax
Project_management (in_dataset, out_dataset, out_coor_system, {transform_method}, {in_coor_system}, {preserve_shape}, {max_deviation})| Parameter | Explanation | Data Type |
in_dataset | The feature class, feature layer, or feature dataset to be projected. | Feature Layer; Feature Dataset |
out_dataset | The output dataset to which the results will be written. | Feature Class; Feature Dataset |
out_coor_system | Valid values are a Spatial Reference object, a file with a .prj extension, or a string representation of a coordinate system. | Coordinate System |
transform_method (Optional) | This method can be used for converting data between two geographic coordinate systems or datums. This optional parameter may be required if the input and output coordinate systems have different datum. | String |
in_coor_system (Optional) | The coordinate system of the input feature class or dataset. When the input has an unknown, or unspecified, coordinate system, this allows you to specify the data's coordinate system without having to modify the input data (which may not be possible if the input is in read-only format). | Coordinate System |
preserve_shape (Optional) | Adds vertices to the output lines or polygons so their projected shape is more accurate.
| Boolean |
max_deviation (Optional) | Determines how far a projected line or polygon can deviate from its exact projected location when preserve_shape = "PRESERVE_SHAPE". The default is 100 times the XY tolerance of the spatial reference of the output dataset. | Linear unit |
Code sample
Project example 1 (Python window)
The following Python window script demonstrates how to use the Project function in immediate mode.
import arcpy
# input data is in NAD 1983 UTM Zone 11N coordinate system
input_features = r"C:/data/Redlands.shp"
# output data
output_feature_class = r"C:/data/Redlands_Project.shp"
# create a spatial reference object for the output coordinate system
out_coordinate_system = arcpy.SpatialReference('NAD 1983 StatePlane California V FIPS 0405 (US Feet)')
# run the tool
arcpy.Project_management(input_features, output_feature_class, out_coordinate_system)
Project example 2 (stand-alone script)
The following stand-alone script demonstrates how to use Project in a stand-alone script.
# Name: Project_Example2.py
# Description: Project all feature classes in a geodatabase
# Requirements: os module
# Import system modules
import arcpy
import os
# Set environment settings
arcpy.env.workspace = "C:/data/Redlands.gdb"
arcpy.env.overwriteOutput = True
# Set local variables
outWorkspace = "C:/data/Redlands_utm11.gdb"
try:
# Use ListFeatureClasses to generate a list of inputs
for infc in arcpy.ListFeatureClasses():
# Determine if the input has a defined coordinate system, can't project it if it does not
dsc = arcpy.Describe(infc)
if dsc.spatialReference.Name == "Unknown":
print ('skipped this fc due to undefined coordinate system: ' + infc)
else:
# Determine the new output feature class path and name
outfc = os.path.join(outWorkspace, infc)
# Set output coordinate system
outCS = arcpy.SpatialReference('NAD 1983 UTM Zone 11N')
# run project tool
arcpy.Project_management(infc, outfc, outCS)
# check messages
print(arcpy.GetMessages())
except arcpy.ExecuteError:
print(arcpy.GetMessages(2))
except Exception as ex:
print(ex.args[0])
Environments
Licensing information
- ArcGIS for Desktop Basic: Yes
- ArcGIS for Desktop Standard: Yes
- ArcGIS for Desktop Advanced: Yes