ArcObjects Library Reference (GeoAnalyst)  

IInterpolationOp.IDW Method

Interpolates using IDW.

[Visual Basic .NET]
Public Function IDW ( _
    ByVal geoData As IGeoDataset, _
    ByVal power As Double, _
    ByVal radius As IRasterRadius, _
    [ByRef barrier As Object] _
) As IGeoDataset
public IGeoDataset IDW (
    IGeoDataset geoData,
    double power,
    IRasterRadius radius,
    ref object barrier

Optional Values

barrier   To indicate that this parameter is undefined, first define a variable object Missing = Type.Missing; then pass this in as ref Missing.
  IGeoDataset* geoData,
  double power,
  IRasterRadius* radius,
  VARIANT* barrier,
  IGeoDataset** GeoDataset


geoData [in]

  geoData is a parameter of type IGeoDataset

power [in]   power is a parameter of type double radius [in]

  radius is a parameter of type IRasterRadius

barrier [optional]   barrier is a parameter of type VARIANT

  To indicate this parameter is undefined pass a reference to a VARIANT with type VT_ERROR and scode value of DISP_E_PARAMNOTFOUND.

GeoDataset [out, retval]

  GeoDataset is a parameter of type IGeoDataset

Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.



an input FeatureClass or FeatureClassDescriptor containing the points with z values to be interpolated onto a surface Raster


exponent of distance. Controls the significance of surrounding points upon the interpolated value. A higher power results in less influence from distant points. It can be any real number greater than zero but the most reasonable results will be obtained using values from 0.5 to 3. A commonly used power is 2


an IRasterRadius indicating the search radius for the input points. The radius distance is specified in map units within which all input sample points will be used to perform interpolation. A commonly used radius is five times the cell size of the output Raster

The object will set and use whatever you set last in your VB script. For example,

set pRad.SetFixed 207.1
set pRad.SetVariable 12
will use the args ... ,SAMPLE,12, ....
set pRad.SetVariable 12
set pRad.SetFixed 207.1
will use the args ... ,RADIUS,207.1, ....


a shapefile containing arcs to be used as a break or limit in searching for the input sample points

See Also

IInterpolationOp Interface