ETG_IDW

Inverse Distance Weighted (IDW) Interpolation

Uses Inverse Distance Weighted Interpolation (IDW) to interpolate a raster from the input features.

Input point or polyline feature dataset.
Output raster name and format.
Cell Size of the output raster.
Value field - a field from the attribute table to be used as a source for the values of the raster. If the input is of PointZ or PolylineZ type, the Z values of the features can be used as source for the raster values.
Power - A positive number that defines the weight of the distance in the interpolation process. The weight of each known point decreases as the distance from it to the interpolated cell increases. The higher the value of the Power, the faster the weight of the known point decreases. If the Power is less than 1 the appearance of the resulting surface will be sharper. If the value of the Power is greater than 1 the appearance of the surface will be smoother. Very large values of the Power will result of a surface with only few known points influencing the value of the interpolated cell. The most commonly used value is 2 (default).
Number of sources - the number of known points to be used in the interpolation of the value of each cell. The default value is 12.
Cut off distance (optional) - a known point will not influence the interpolation of cells that are farther than this distance from the point. The default value is 0 meaning that no cut off distance will be used.

Output raster - Power = 0.5.

Output raster - Power = 2.

Output raster - Power = 15.

When the value in the Value field is NULL, it is interpreted as 0 for the IDW calculations.
The input format accepted are file based rasters - ERDAS IMAGINE or Tagged Image File Format (TIFF).
The .NET ToolBox for ArcGIS Desktop accepts also FileGDB Raster inputs.
For file based rasters initially the name of the output raster define the raster format:
- .img extension (for example raster1.img) - ERDAS IMAGINE image.
- .tif extension (for example raster1.tif) - TIFF image.
- The initial output raster format can be changed by selecting the desired output in the dialog.

Parameters

Expression	Explanation
Function Name	IDW
<input dataset>	A String representing the input layer. Must be of Point or Polyline type.
<output raster>	A String - the full name of the output raster.
<cell size>	A Double representing the cell size of the output raster.
<value field>	A String representing the name of the field which values are going to be used for interpolation.
<power>	A Number - see main description above.
<number of sources>	A Number - see main description above.
{cutoff distance}	A Double representing the Cutoff distance.

ETSPath used in the table below is the full path to ETSRun.exe (E.G. "C:\Program Files\ETSpatial Techniques\ETSurface\ETSRun.exe")

Language	Syntax
Python	subprocess.call([ETSPath, "IDW", "input dataset", "output raster", "cell size", "value field", "power", "number of sources", "cutoff distance"])
.NET using ETSRun.exe	StartInfo.FileName = ETSPath StartInfo.Arguments = "IDW" "input dataset" "output raster" "cell size" "value field" "power" "number of sources" "cutoff distance"
.NET using ETSOutX.dll	IDW(input dataset, output raster, cell size, value field, power, number of sources, cutoff distance)
ArcPy	arcpy.IDW("input dataset", "output raster", "cell size", "value field", "power", "number of sources", "cutoff distance")

Notes:

<> - required parameter
{} - optional parameter
See examples for Python , .NET or ArcPy
The argument separator for StartInfo.Arguments is space. If a string might contain a space, you need to double quote it.