com.esri.arcgis.geoprocessing.tools.spatialstatisticstools
Class StandardDistance

java.lang.Object
  com.esri.arcgis.geoprocessing.AbstractGPTool
      com.esri.arcgis.geoprocessing.tools.spatialstatisticstools.StandardDistance

All Implemented Interfaces:

GPTool

public class StandardDistance
extends AbstractGPTool

Measures the degree to which features are concentrated or dispersed around the geometric mean center. The Standard Distance tool is contained in the Spatial Statistics Tools tool box.

Usage tips:

• The standard distance is a useful statistic as it provides a single summary measure of feature distribution around their center (similar to the way a standard deviation measures the distribution of data values around the statistical mean).
• The Standard Distance tool creates a new feature class containing a circle polygon centered on the mean for each case. Each circle polygon is drawn with a radius equal to the standard distance. The attribute value for each circle polygon is its standard distance value.
• The Case Field is used to group features prior to analysis. When a Case Field is specified, the input features are first grouped according to case field values, and then a standard distance circle is computed for each group. The case field can be of numeric, date, or string type, and will appear as an attribute in the Output Feature Class.
• The standard distance calculation may be based on an optional Weight Field (to get the standard distance of businesses weighted by employees, for example). The Weight Field should be numeric.
• If the underlying spatial pattern of the input features is concentrated in the center with fewer features toward the periphery (spatial normal distribution), a one standard deviation circle polygon will cover approximately 68 percent of the features; a two standard deviation circle will contain approximately 95 percent of the features; and three standard deviations will cover approximately 99 percent of the features in the cluster.
• Calculations based on either Euclidean or Manhattan distance require to accurately measure distances.
• For line and polygon features, feature centroids are used in distance computations. For multipoints, polylines, or polygons with multiple parts, the centroid is computed using the weighted mean center of all feature parts. The weighting for point features is 1, for line features is length, and for polygon features is area.
• Map layers can be used to define the Input Feature Class. When using a layer with a selection, only the selected features are included in the analysis.
• When using shapefiles, keep in mind that they cannot store null values. Tools or other procedures that create shapefiles from non-shapefile inputs may store or interpret null values as zero. This can lead to unexpected results. See also .

Field Summary

Fields inherited from class com.esri.arcgis.geoprocessing.AbstractGPTool

vals

Constructor Summary

StandardDistance()
Creates the Standard Distance tool with defaults.

StandardDistance(Object inputFeatureClass, Object outputStandardDistanceFeatureClass, String circleSize)
Creates the Standard Distance tool with the required parameters.

Method Summary

Object	getCaseField() Returns the Case Field parameter of this tool .
String	getCircleSize() Returns the Circle Size parameter of this tool .
Object	getInputFeatureClass() Returns the Input Feature Class parameter of this tool .
Object	getOutputStandardDistanceFeatureClass() Returns the Output Standard Distance Feature Class parameter of this tool .
String	getToolboxAlias() Returns the alias of the tool box containing this tool.
String	getToolboxName() Returns the name of the tool box containing this tool.
String	getToolName() Returns the name of this tool.
Object	getWeightField() Returns the Weight Field parameter of this tool .
void	setCaseField(Object caseField) Sets the Case Field parameter of this tool .
void	setCircleSize(String circleSize) Sets the Circle Size parameter of this tool .
void	setInputFeatureClass(Object inputFeatureClass) Sets the Input Feature Class parameter of this tool .
void	setOutputStandardDistanceFeatureClass(Object outputStandardDistanceFeatureClass) Sets the Output Standard Distance Feature Class parameter of this tool .
void	setWeightField(Object weightField) Sets the Weight Field parameter of this tool .

Methods inherited from class com.esri.arcgis.geoprocessing.AbstractGPTool

getParameterValues, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

StandardDistance

public StandardDistance()

Creates the Standard Distance tool with defaults.

Initializes the array of tool parameters with the default values specified when the tool was created.

StandardDistance

public StandardDistance(Object inputFeatureClass,
                        Object outputStandardDistanceFeatureClass,
                        String circleSize)

Creates the Standard Distance tool with the required parameters.

Initializes the array of tool parameters with the values as specified for the required parameters and with the default values for the other parameters.

Parameters:

inputFeatureClass - a feature class containing a distribution of features for which the standard distance will be calculated.

outputStandardDistanceFeatureClass - a polygon feature class that will contain a circle polygon for each input center. These circle polygons graphically portray the standard distance at each center point.

circleSize - the size of output circles in standard deviations. The default circle size is 1; valid choices are 1, 2, or 3 standard deviations.

Method Detail

getInputFeatureClass

public Object getInputFeatureClass()

Returns the Input Feature Class parameter of this tool . This parameter is a feature class containing a distribution of features for which the standard distance will be calculated. This is a required parameter.

Returns:

the Input Feature Class

setInputFeatureClass

public void setInputFeatureClass(Object inputFeatureClass)

Sets the Input Feature Class parameter of this tool . This parameter is a feature class containing a distribution of features for which the standard distance will be calculated. This is a required parameter.

Parameters:

inputFeatureClass - a feature class containing a distribution of features for which the standard distance will be calculated.

getOutputStandardDistanceFeatureClass

public Object getOutputStandardDistanceFeatureClass()

Returns the Output Standard Distance Feature Class parameter of this tool . This parameter is a polygon feature class that will contain a circle polygon for each input center. These circle polygons graphically portray the standard distance at each center point. This is a required parameter.

Returns:

the Output Standard Distance Feature Class

setOutputStandardDistanceFeatureClass

public void setOutputStandardDistanceFeatureClass(Object outputStandardDistanceFeatureClass)

Sets the Output Standard Distance Feature Class parameter of this tool . This parameter is a polygon feature class that will contain a circle polygon for each input center. These circle polygons graphically portray the standard distance at each center point. This is a required parameter.

Parameters:

outputStandardDistanceFeatureClass - a polygon feature class that will contain a circle polygon for each input center. These circle polygons graphically portray the standard distance at each center point.

getCircleSize

public String getCircleSize()

Returns the Circle Size parameter of this tool . This parameter is the size of output circles in standard deviations. The default circle size is 1; valid choices are 1, 2, or 3 standard deviations. This is a required parameter.

Returns:

the Circle Size

setCircleSize

public void setCircleSize(String circleSize)

Sets the Circle Size parameter of this tool . This parameter is the size of output circles in standard deviations. The default circle size is 1; valid choices are 1, 2, or 3 standard deviations. This is a required parameter.

Parameters:

circleSize - the size of output circles in standard deviations. The default circle size is 1; valid choices are 1, 2, or 3 standard deviations.

getWeightField

public Object getWeightField()

Returns the Weight Field parameter of this tool . This parameter is the numeric field used to weight locations according to their relative importance. This is an optional parameter.

Returns:

the Weight Field

setWeightField

public void setWeightField(Object weightField)

Sets the Weight Field parameter of this tool . This parameter is the numeric field used to weight locations according to their relative importance. This is an optional parameter.

Parameters:

weightField - the numeric field used to weight locations according to their relative importance.

getCaseField

public Object getCaseField()

Returns the Case Field parameter of this tool . This parameter is field used to group features for separate standard distance calculations. The case field can be of numeric, date, or string type. This is an optional parameter.

Returns:

the Case Field

setCaseField

public void setCaseField(Object caseField)

Sets the Case Field parameter of this tool . This parameter is field used to group features for separate standard distance calculations. The case field can be of numeric, date, or string type. This is an optional parameter.

Parameters:

caseField - field used to group features for separate standard distance calculations. The case field can be of numeric, date, or string type.

getToolName

public String getToolName()

Returns the name of this tool.

Returns:

the tool name

getToolboxName

public String getToolboxName()

Returns the name of the tool box containing this tool.

Returns:

the tool box name

getToolboxAlias

public String getToolboxAlias()

Returns the alias of the tool box containing this tool.

Returns:

the tool box alias