Interpolate Shape (3D Analyst)

Available with 3D Analyst license.

Available with Spatial Analyst license.

Summary

Creates 3D features by interpolating z-values from a surface.

Learn more about how Interpolate Shape works

Illustration

Interpolate Shape tool illustration

Usage

  • This tool creates 3D features using height values derived from overlapping portions of the input surface. A 3D polygon will only store z-values on its perimeter, since the interior of a 3D polygon will be randomly defined when it is rendered. For this reason, 3D polygons are generally not suitable for representing nonplanar height information. To generate a true representation of the surface, use the Interpolate Polygon To Multipatch tool.

  • Any curved line or polygon segments will be densified based on the Sampling Distance parameter value. If a sampling distance is not defined, this value will be derived from the input surface. For a raster, the default sampling size will be the raster's cell size. For a TIN, terrain, or LAS dataset, the default sampling will be based on the edges produced by the triangulated surface. If the curve is shorter than the sampling size, the curve will be simplified into a two-point line using its start and end points.

  • When using natural neighbors interpolation, consider specifying a sampling distance that's equal to or above half of the average point spacing of the data points in the surface.

  • When using the Interpolate Vertices Only parameter, features with vertices that fall outside the data area of the surface will not be part of the output unless the input surface is a raster and the nearest neighbor interpolation method is used.

Parameters

LabelExplanationData Type
Input Surface

The surface that will be used for interpolating z-values.

LAS Dataset Layer; Mosaic Layer; Raster Layer; Terrain Layer; TIN Layer; Image Service
Input Features

The input features to process.

Feature Layer
Output Feature Class

The feature class that will be produced.

Feature Class
Sampling Distance
(Optional)

The spacing at which z-values will be interpolated. By default, this is a raster dataset's cell size or a triangulated surface's natural densification.

Double
Z Factor
(Optional)

The factor by which z-values will be multiplied. This is typically used to convert z linear units to match x,y linear units. The default is 1, which leaves elevation values unchanged. This parameter is not available if the spatial reference of the input surface has a z datum with a specified linear unit.

Double
Method
(Optional)

Specifies the interpolation method that will be used to determine elevation values for the output features. The available options depend on the surface type.

  • BilinearThe value of the query point will be determined using bilinear interpolation. This is the default when the input is a raster surface.
  • Nearest NeighborThe value of the query point will be determined using nearest neighbor interpolation. With this method, surface values will only be interpolated for the input feature's vertices. This option is only available for a raster surface.
  • LinearElevation values will be obtained from the plane defined by the triangle that contains the x,y-location of a query point. This is the default interpolation method for TIN, terrain, and LAS datasets.
  • Natural NeighborsElevation values will be obtained by applying area-based weights to the natural neighbors of a query point.
  • Conflate Minimum Z Elevation values will be obtained from the smallest z-value found among the natural neighbors of a query point.
  • Conflate Maximum ZElevation values will be obtained from the largest z-value found among the natural neighbors of a query point.
  • Conflate Nearest Z Elevation values will be obtained from the nearest value among the natural neighbors of a query point.
  • Conflate Z Closest To Mean Elevation values will be obtained from the z-value that is closest to the average of all the natural neighbors of a query point.
String
Interpolate Vertices Only
(Optional)

Specifies whether the interpolation will only occur along the vertices of an input feature, ignoring the sample distance option. When the input surface is a raster and the nearest neighbor interpolation method is selected, the z-values can only be interpolated at the feature vertices.

  • Checked—Interpolation will only occur along the vertices.
  • Unchecked—Interpolation will occur using the sampling distance. This is the default.
Boolean
Pyramid Level Resolution
(Optional)

The z-tolerance or window-size resolution of the terrain pyramid level that will be used. The default is 0, or full resolution.

Double
Preserve features partially outside surface
(Optional)

Specifies whether features with one or more vertices that fall outside the raster's data area will be retained in the output. This parameter is only available when the input surface is a raster and the nearest neighbor interpolation method is used.

  • Checked—Each vertex that falls outside the raster surface will have its z-value derived from the trend of z-values calculated for the vertices within the raster surface and will be retained in the output.
  • Unchecked—Features with at least one vertex that falls outside the raster surface will be skipped in the output. This is the default.
Boolean

arcpy.ddd.InterpolateShape(in_surface, in_feature_class, out_feature_class, {sample_distance}, {z_factor}, {method}, {vertices_only}, {pyramid_level_resolution}, {preserve_features})
NameExplanationData Type
in_surface

The surface that will be used for interpolating z-values.

LAS Dataset Layer; Mosaic Layer; Raster Layer; Terrain Layer; TIN Layer; Image Service
in_feature_class

The input features to process.

Feature Layer
out_feature_class

The feature class that will be produced.

Feature Class
sample_distance
(Optional)

The spacing at which z-values will be interpolated. By default, this is a raster dataset's cell size or a triangulated surface's natural densification.

Double
z_factor
(Optional)

The factor by which z-values will be multiplied. This is typically used to convert z linear units to match x,y linear units. The default is 1, which leaves elevation values unchanged. This parameter is not available if the spatial reference of the input surface has a z datum with a specified linear unit.

Double
method
(Optional)

Specifies the interpolation method that will be used to determine elevation values for the output features. The available options depend on the surface type.

  • BILINEARThe value of the query point will be determined using bilinear interpolation. This is the default when the input is a raster surface.
  • NEARESTThe value of the query point will be determined using nearest neighbor interpolation. With this method, surface values will only be interpolated for the input feature's vertices. This option is only available for a raster surface.
  • LINEARElevation values will be obtained from the plane defined by the triangle that contains the x,y-location of a query point. This is the default interpolation method for TIN, terrain, and LAS datasets.
  • NATURAL_NEIGHBORSElevation values will be obtained by applying area-based weights to the natural neighbors of a query point.
  • CONFLATE_ZMIN Elevation values will be obtained from the smallest z-value found among the natural neighbors of a query point.
  • CONFLATE_ZMAXElevation values will be obtained from the largest z-value found among the natural neighbors of a query point.
  • CONFLATE_NEAREST Elevation values will be obtained from the nearest value among the natural neighbors of a query point.
  • CONFLATE_CLOSEST_TO_MEAN Elevation values will be obtained from the z-value that is closest to the average of all the natural neighbors of a query point.
String
vertices_only
(Optional)

Specifies whether the interpolation will only occur along the vertices of an input feature, ignoring the sample distance option.

  • DENSIFYInterpolation will occur using the sampling distance. This is the default.
  • VERTICES_ONLYInterpolation will only occur along the vertices.
Boolean
pyramid_level_resolution
(Optional)

The z-tolerance or window-size resolution of the terrain pyramid level that will be used. The default is 0, or full resolution.

Double
preserve_features
(Optional)

Specifies whether features with one or more vertices that fall outside the raster's data area will be retained in the output. This parameter is only available when the input surface is a raster and the nearest neighbor interpolation method is used.

  • PRESERVEEach vertex that falls outside the raster surface will have its z-value derived from the trend of z-values calculated for the vertices within the raster surface and will be retained in the output.
  • EXCLUDEFeatures with at least one vertex that falls outside the raster surface will be skipped in the output. This is the default.
Boolean

Code sample

InterpolateShape example 1 (Python window)

The following sample demonstrates the use of this tool in the Python window.

arcpy.env.workspace = "C:/data"
arcpy.ddd.InterpolateShape("my_tin", "roads.shp", "roads_interp.shp")
InterpolateShape example 2 (stand-alone script)

The following sample demonstrates the use of this tool in a stand-alone Python script.

'''*********************************************************************
Name: InterpolateShape Example
Description: This script demonstrates how to use InterpolateShape
             on all 2D features in a target workspace.
*********************************************************************'''
# Import system modules
import arcpy

# Set local variables
inWorkspace = arcpy.GetParameterAsText(0)
surface = arcpy.GetParameterAsText(1)

try:
    # Set default workspace
    arcpy.env.workspace = inWorkspace
    # Create list of feature classes in target workspace
    fcList = arcpy.ListFeatureClasses()
    if fcList:
        for fc in fcList:
            desc = arcpy.Describe(fc)
            # Find 2D features
            if not desc.hasZ:
                # Set Local Variables
                outFC = "{0}_3D.shp".format(desc.basename)
                method = "BILINEAR"
                # Execute InterpolateShape
                arcpy.ddd.InterpolateShape(surface, fc, outFC, 
                                           10, 1, method, True)
            else:
                print("{0} is not a 2D feature.".format(fc))
    else:
        print("No feature classes were found in {0}.".format(env.workspace))
    
except arcpy.ExecuteError:
    print(arcpy.GetMessages())
    
except Exception as err:
    print(err)

Licensing information

  • Basic: Requires 3D Analyst
  • Standard: Requires 3D Analyst
  • Advanced: Requires 3D Analyst

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