com.esri.arcgis.spatialanalyst
Interface IDensityOp

All Superinterfaces:
Serializable
All Known Implementing Classes:
RasterDensityOp

public interface IDensityOp
extends Serializable

Provides access to members that control the density operations.

Remarks

  • Read the Working with ArcGIS Spatial Analyst objects technical document for general information on implementing Spatial Analyst operations.
  • Product Availability

    Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server. Requires Spatial Analyst Extension.

    Supported Platforms

    Windows, Solaris, Linux


    Method Summary
     IGeoDataset kernelDensity(IGeoDataset sourceFeatures, Object radiusDistance, Object scaleFactor)
              Calculates the kernel density of points or lines in a radius around each output cell.
     IGeoDataset lineDensity(IGeoDataset lineFeatures, Object radiusDistance, Object scaleFactor)
              Calculates the simple density of lines in a radius around each output cell.
     IGeoDataset pointDensity(IGeoDataset pointFeatures, IRasterNeighborhood nbrhood, Object scaleFactor)
              Calculates the simple density of points in a neighborhood around each output cell.
     

    Method Detail

    pointDensity

    IGeoDataset pointDensity(IGeoDataset pointFeatures,
                             IRasterNeighborhood nbrhood,
                             Object scaleFactor)
                             throws IOException,
                                    AutomationException
    Calculates the simple density of points in a neighborhood around each output cell. Density is measured as number of points per unit area.

    Remarks

    sourceFeatures

    Input point or polyline featureclass, featureclass descriptor or featureDataset used to calculates the density of features around each output cell.

    For density functions, SPOT is the default field used when no field has been specified. If a SPOT field does not exist, then no field will be used, and each feature will be counted only once in the calculation. This is similar to specifying a keyword for the field of "NONE". If a field other than NONE is used, the field's value (the item value) determines the number of times to count the point. To specify the field you want form your dataset, use the FeatureClassDescriptor object.

    nbrhood

    An IRasterNeighborhood defining the configuration of the neighborhoods within which the point desnity will be calculated.
    IDensityOp:PointDensity supports any supports any neighborhood supported by IRasterNeighborhood. They include a rectangle, circle, annulus, wedge, and an irregular shaped neighborhood. The neighborhood will be defined by the minimum-bounding rectangle of the specified neighborhood. The minimum-bounding rectangle will include more cells then the specified neighborhood in certain cases such as with a circle, annulus, and wedge.

    The neighborhoods types are:

    SetAnnulus (innerRadius As Double, outerRadius As Double, unitsType as esriGeoAnalysisUnitsEnum)

    SetCircle (radius As Double, unitsType as esriGeoAnalysisUnitsEnum)

    SetDefault ()

    SetIrregular (height As Long, width As Long, entryValues)

    [scaleFactor]

    Used to convert the map units of the input dataset to different units. The default value is 1, which calculates density in units of number of points per one square map unit. Effectively, output raster values are multiplied by the square of this factor.

    Product Availability

    Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server. Requires Spatial Analyst Extension.

    Supported Platforms

    Windows, Solaris, Linux

    Parameters:
    pointFeatures - A reference to a com.esri.arcgis.geodatabase.IGeoDataset (in)
    nbrhood - A reference to a com.esri.arcgis.geoanalyst.IRasterNeighborhood (in)
    scaleFactor - A Variant (in, optional, pass null if not required)
    Returns:
    A reference to a com.esri.arcgis.geodatabase.IGeoDataset
    Throws:
    IOException - If there are interop problems.
    AutomationException - If the ArcObject component throws an exception.

    lineDensity

    IGeoDataset lineDensity(IGeoDataset lineFeatures,
                            Object radiusDistance,
                            Object scaleFactor)
                            throws IOException,
                                   AutomationException
    Calculates the simple density of lines in a radius around each output cell. Density is measured as length of lines per unit area.

    Remarks

    lineFeatures

    Input polyline featureclass, featureclass descriptor or featureDataset used to calculate the density of lines features around each output cell.

    For density functions, SPOT is the default field used when no field has been specified. If a SPOT field does not exist, then no field will be used, and each feature will be counted only once in the calculation. This is similar to specifying a keyword for the field of "NONE". If a field other than NONE is used, the length of the line is considered to be its actual length times the value of the field for that line. To specify the field use the FeatureClassDescriptor object.

    [radiusDistance]

    A circular neighborhood with the given radius. The default radius is calculated so that all cells in the output grid have at least one point within the neighborhood.

    [scaleFactor]

    Used to convert the map units of the input dataset to different units. The default value is 1, which calculates density in units of number of points per one square map unit. Effectively, output raster values are multiplied by the square of this factor.

    Product Availability

    Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server. Requires Spatial Analyst Extension.

    Supported Platforms

    Windows, Solaris, Linux

    Parameters:
    lineFeatures - A reference to a com.esri.arcgis.geodatabase.IGeoDataset (in)
    radiusDistance - A Variant (in, optional, pass null if not required)
    scaleFactor - A Variant (in, optional, pass null if not required)
    Returns:
    A reference to a com.esri.arcgis.geodatabase.IGeoDataset
    Throws:
    IOException - If there are interop problems.
    AutomationException - If the ArcObject component throws an exception.

    kernelDensity

    IGeoDataset kernelDensity(IGeoDataset sourceFeatures,
                              Object radiusDistance,
                              Object scaleFactor)
                              throws IOException,
                                     AutomationException
    Calculates the kernel density of points or lines in a radius around each output cell. A kernel function is used to distribute density values around each point or line.

    Remarks

    pointFeatures

    Input point featureclass, featureclass descriptor or featureDataset used to calculate the density of point features around each output cell.

    For density functions, SPOT is the default field used when no field has been specified. If a SPOT field does not exist, then no field will be used, and each feature will be counted only once in the calculation. This is similar to specifying a keyword for the field of "NONE". If a field other than NONE is used, the field's value (the item value) determines the number of times to count the point. To specify the field use the FeatureClassDescriptor object.

    [radiusDistance]

    A circular neighborhood with the given radius. The default radius is calculated so that all cells in the output grid have at least one point within the neighborhood.

    [scaleFactor]

    Used to convert the map units of the input dataset to different units. The default value is 1, which calculates density in units of number of points per one square map unit. Effectively, output raster values are multiplied by the square of this factor.

    Product Availability

    Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server. Requires Spatial Analyst Extension.

    Supported Platforms

    Windows, Solaris, Linux

    Parameters:
    sourceFeatures - A reference to a com.esri.arcgis.geodatabase.IGeoDataset (in)
    radiusDistance - A Variant (in, optional, pass null if not required)
    scaleFactor - A Variant (in, optional, pass null if not required)
    Returns:
    A reference to a com.esri.arcgis.geodatabase.IGeoDataset
    Throws:
    IOException - If there are interop problems.
    AutomationException - If the ArcObject component throws an exception.