Near (Analysis) (ArcInfo only)

Usage tips

• The Input Features can be one of the following feature types:

  • POINT
  • POLYLINE
  • POLYGON
  • MULTIPOINT

• The Near Features can include one or more feature classes of different types.

• The results are recorded in the Input Features attribute table. Fields for distance and feature ID of the closest feature are added or updated. The field names are

  • NEAR_FID: The FID of the Near Feature
  • NEAR_DIST: Distance between the Input Features and the Near Features
  • NEAR_X: X-coordinate of the NEAR_FID feature (This field is not added by default; see Location parameter help for details.)
  • NEAR_Y: Y-coordinate of the NEAR_FID feature (This field is not added by default; see Location parameter help for details.)
  • NEAR_ANGLE: Angle between the input and near feature (This field is not added by default; see Angle parameter help for details.)
  • NEAR_FC: The path name of the layer or feature class (This field is only used when multiple Near Features are specified.)

• The values for NEAR_DIST will be -1 if no match is found within the Search Radius.

• The values for NEAR_FID will be -1 if no match is found within the specified Search Radius.

• If the fields NEAR_DIST and NEAR_FID already exist, the values will be recalculated.

• If no Search Radius is specified, a radius large enough to calculate a distance from each input feature to the closest near feature will be used.

• If the Near Features are polylines, the distance is calculated from the location on the polyline closest to the Input Feature. If a polyline in the Near Features touches or intersects a feature from the Input Features, the distance will be zero.

• If the Near Features is a Polygon feature class, the distance is calculated from a point on the boundary of the polygon closest to the Input Feature. If a polygon in the Near Features contains or intersects a feature from the Input Features, the distance will be zero.

• The distances calculated by Near are determined by the units of the Input Features. If the linear units of the input feature class are in Meters, the Search Radius will default to Meters. The units of the Search Radius can be changed. Specifying one kilometer is the same as entering one thousand meters. However, the value for the NEAR_DIST will be based on the units of the input.

• Angles are measured in degrees, where one degree represents 1/360 of a circle, and fractions of a degree are represented as decimal points. Angles are measured from 180° to -180° ; 0° to the east, 90° to the north, 180° (-180° ) to the west, and -90° to the south.

• Both the Input Features and Near Features can be the same dataset. In any instance where the Input Feature and Near feature are the same, the result will be calculated to -1.

• The Input Features can be a layer on which you have performed a selection. The selected features will be used and updated during the execution of Near. The remaining features will have their values set to -1.

• The following environment affects this tool: Extent.

Command line syntax
An overview of the Command Line window
Near_analysis <in_features> <near_features> {search_radius} {NO_LOCATION | LOCATION} {NO_ANGLE | ANGLE}

Command line example

Near_analysis D:\Workspace\wells.shp D:\Workspace\seis.shp 25000 LOCATION ANGLE

Scripting syntax
About getting started with writing geoprocessing scripts
Near_analysis (in_features, near_features, search_radius, location, angle)

Script example

import arcgisscripting
gp = arcgisscripting.create()

gp.workspace = "D:/Workspace"
gp.toolbox = "analysis"
gp.near("wells.shp", "seismic.shp", "25000", "LOCATION", "ANGLE")