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Table To Ellipse

Summary

Creates a new feature class containing geodetic ellipse features constructed based on the values in an x-coordinate field, y-coordinate field, major-axis field, minor-axis field, and azimuth field of a table.

Illustration

Table To Ellipse overview graphic
Ellipse construction parameters

Usage

  • If you use text files and .csv (comma-separated value) files as input, make sure that they follow the file structure specified in About tabular data sources.

  • Each geodetic ellipse is constructed using a particular set of field values representing the x and y coordinates of a center point, major and minor axis lengths, and azimuth angle measured from North. These fields and values will be included in the output.

  • A geodetic ellipse is a curve on the surface of the earth. However, a geodetic ellipse feature is not stored as a parametric (true) curve in the output, but rather a densified polyline representing the path of the geodetic ellipse.

  • If you specify the same field for both Major Field and Minor Field, or if the values in both fields are equal, then the output features represent geodetic circles.

  • When the output is a feature class in a file geodatabase or a personal geodatabase, the values in the Shape_Length field are always in the units of the output coordinate system specified by the Spatial Reference parameter; and they are the planar lengths of the polylines. To measure a geodesic length or distance, use the ArcMap Measure tool; make sure to choose the Geodesic, Loxodrome, or Great Elliptic option accordingly before taking a measurement.

  • When needed, you can use the Feature To Polygon tool to convert the output polylines to polygons.

Syntax

TableToEllipse_management (in_table, out_featureclass, x_field, y_field, major_field, minor_field, distance_units, {azimuth_field}, {azimuth_units}, {id_field}, {spatial_reference})
ParameterExplanationData Type
in_table

The input table that can be a text file, CSV file, Excel file, dBASE table, or geodatabase table.

Table View
out_featureclass

The output feature class containing geodetic ellipses as densified polylines.

Feature Class
x_field

A numerical field in the input table containing the x coordinates (or longitudes) of the center points of ellipses to be positioned in the output coordinate system specified by the spatial_reference parameter.

Field
y_field

A numerical field in the input table containing the y coordinates (or latitudes) of the center points of ellipses to be positioned in the output coordinate system specified by the spatial_reference parameter.

Field
major_field

A numerical field in the input table containing major axis lengths of the ellipses.

Field
minor_field

A numerical field in the input table containing minor axis lengths of the ellipses.

Field
distance_units

The units for the values in Major Field and Minor Field.

  • METERS
  • KILOMETERS
  • MILES
  • NAUTICAL_MILES
  • FEET
  • US_SURVEY_FEET
String
azimuth_field
(Optional)

A numerical field in the input table containing azimuth angle values for the major axis rotations of the output ellipses. The values are measured clockwise from North.

Field
azimuth_units
(Optional)

The units of the values in the Azimuth Field.

  • DEGREES —Values in decimal degrees; this is the default.
  • MILS —Values in mils.
  • RADS —Values in radians.
  • GRADS —Values in gradians.
String
id_field
(Optional)

A field in the input table; this field and the values are included in the output and can be used to join the output features with the records in the input table.

Field
spatial_reference
(Optional)

The spatial reference of the output feature class. You can specify the spatial reference in several ways:

  • By entering the path to a .prj file, such as C:/workspace/watershed.prj.
  • By referencing a feature class or feature dataset whose spatial reference you want to apply, such as C:/workspace/myproject.gdb/landuse/grassland.
  • By defining a spatial reference object prior to using this tool, such as sr = arcpy.SpatialReference("C:/data/Africa/Carthage.prj"), which you then use as the spatial reference parameter.

Spatial Reference

Code sample

TableToEllipse example (stand-alone script)

Creates polyline ellipse features from a table.

# Import system modules
import arcpy
from arcpy import env

# Set local variables
input_table = r"c:\workspace\SGS\eltop.gdb\elret"
output_ellipse = r"c:\workspace\SGS\eltop.gdb\Eplyln_001"

#Table To Ellipse
arcpy.TableToEllipse_management(input_table, output_ellipse, "lond",
                                "latd", "mjerr", "mnerr", "KILOMETERS",
                                "orient", "DEGREES", "LinkID")

Environments

Licensing information

  • ArcGIS for Desktop Basic: Yes
  • ArcGIS for Desktop Standard: Yes
  • ArcGIS for Desktop Advanced: Yes

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