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Validate Spot Heights (Topographic Production)

In this topic

  1. Summary
  2. Usage
  3. Parameters
  4. Environments
  5. Licensing information

Summary

Validates that spot heights are higher than or equal to their respective contour top, and based on the contour interval, that a contour top is not missing a contour line between it and a spot height.

Usage

    Caution:

    This tool modifies the input data. See Tools that modify or update the input data for more information and strategies to avoid undesired data changes.

  • This tool identifies features in the Spot Features parameter value that don't pass the validation. Review the values in the IS_VALID field of the selected features.

  • Contour tops refer to an elevation surrounded by lower elevation contour lines. Contour tops must be polylines that start and end at the same vertex.

  • The Contour Interval parameter value is used to determine if there is a missing contour line between the contour top and the spot height. For example, if the Contour Interval parameter value is set to 20 and the elevation difference between the spot height and contour top is 40, the spot height will be selected.

  • This tool will update the values for the IS_VALID field as follows:

    ValueDetails

    0

    Valid

    1

    Not highest point in top

    Note:

    This value can only be returned when the Use Input Rasters for Validation parameter is checked.

    2

    Incorrect contour interval

    3

    Invalid contour or spot elevation

    Note:

    This can occur when a contour is a depression and as a result, the spot's elevation is higher than that of the contour, or vice-versa.

    4

    Spot not in contour

    If the IS_VALID field does not exist on the feature class, the tool will create it.

  • When the Use Input Rasters for Validation parameter is unchecked, it is assumed that all contours are tops and flag spots that are lower than their surrounding contour. The tool will still validate that there is no missing contour line between a contour top and its associated spot height using the Contour Interval parameter value.

  • Using an elevation raster equips the tool with more logic to validate spot heights. The raster is used to identify contour tops and bottoms, as well as compare the raster height values with the height values for the spot heights.

  • Ensure that the height values of the elevation raster closely match the height values of the Input Contours and Input Spot Heights parameter values. The more the elevation values differ, the more likely false positives will be returned by the tool. For best results, use the elevation raster that was used to generate the contour lines and spot heights.

  • If an elevation raster with height values that closely match the height values of the Input Contours and Input Spot Heights parameter values is not available, uncheck the Use Input Rasters for Validation parameter.

Parameters

DialogPython

LabelExplanationData Type
Input Contours

The contour features that will be used to validate the spot heights.

Feature Layer
Contour Height Field

The field that contains elevation values for the Input Contours parameter value. The field type must be numeric.

Field
Contour Interval

The interval, or distance, between contour lines. The value can be any positive number. The default is 20.

Long
Input Rasters

The rasters that will be used to derive elevations of points inside contours.

Raster Layer; Mosaic Layer
Input Spot Features

An existing point feature layer that contains spot heights that will be validated.

Feature Layer
Spot Height Field

The field that contains elevation values for the Input Spot Features parameter value.

Field
Area of Interest
(Optional)

The extent that contains the spot heights that will be validated. This parameter does not accept point layers as valid input and must have only one selected feature.

Feature Layer
Z Factor
(Optional)

The unit conversion factor that will be used when validating spot heights to convert the contour elevation value unit of measurement to match the raster's unit of measurement. The default is 1.

For example, if the input raster's elevation values are in meters but the contours are in feet, set the z-factor to 3.28084 (1 meter = 3.28084 feet).

Double
Use Input Rasters for Validation
(Optional)

Specifies whether the Input Rasters parameter value will be used to validate the spot heights.

  • Checked—The Input Rasters parameter value will be used to validate the spot heights. This is the default.
  • Unchecked—The Input Rasters parameter value will not be used to validate the spot heights.
Boolean

Derived Output

LabelExplanationData Type
Updated Spot Features

The Input Spot Features parameter value with updated attribution for spot heights.

Feature Layer

arcpy.topographic.ValidateSpotHeights(in_contour_features, contour_height_field, contour_interval, in_rasters, in_spot_features, spot_height_field, {area_of_interest}, {z_factor}, {use_rasters})
NameExplanationData Type
in_contour_features

The contour features that will be used to validate the spot heights.

Feature Layer
contour_height_field

The field that contains elevation values for the in_contour_features parameter value. The field type must be numeric.

Field
contour_interval

The interval, or distance, between contour lines. The value can be any positive number. The default is 20.

Long
in_rasters
[in_rasters,...]

The rasters that will be used to derive elevations of points inside contours.

Raster Layer; Mosaic Layer
in_spot_features

An existing point feature layer that contains spot heights that will be validated.

Feature Layer
spot_height_field

The field that contains elevation values for the in_spot_features parameter value.

Field
area_of_interest
(Optional)

The extent that contains the spot heights that will be validated. This parameter does not accept point layers as valid input and must have only one selected feature.

Feature Layer
z_factor
(Optional)

The unit conversion factor that will be used when validating spot heights to convert the contour elevation value unit of measurement to match the raster's unit of measurement. The default is 1.

For example, if the input raster's elevation values are in meters but the contours are in feet, set the z-factor to 3.28084 (1 meter = 3.28084 feet).

Double
use_rasters
(Optional)

Specifies whether the rasters provided will be used to validate the spot heights.

  • USE_RASTERS—The in_rasters parameter value will be used to validate the spot heights. This is the default.
  • NO_USE_RASTERS—The in_rasters parameter value will not be used to validate the spot heights.
Boolean

Derived Output

NameExplanationData Type
updated_spot_features

The in_spot_features parameter value with updated attribution for spot heights.

Feature Layer

Code sample

ValidateSpotHeights example (stand-alone script)

The following stand-alone sample script demonstrates how to run the ValidateSpotHeights function.

# Name: ValidateSpotHeights_sample.py
# Description: Validates that spot heights are higher than or equal to their respective contour top, and based on the contour interval, 
# that a contour top is not missing a contour line between it and a spot height.
    
# Import System Modules
import arcpy

# Check Out Extensions
arcpy.CheckOutExtension('Foundation')

# Setting the environment
arcpy.env.overwriteOutput = True

# Setting Local Variables
in_contour_features = r'C:\Data\TDS_7_1.gdb\TDS_CARTO\HypsographyCrv'
contour_height_field = 'ZVH'
contour_interval = '328'
in_rasters = r'C:\Data\Raster\Elevation.gdb\DEM'
in_spot_features = r'C:\Data\TDS_7_1.gdb\TDS_CARTO\HypsographyPnt'
spot_height_field = 'ZVH'
area_of_interest = r'C:\Users\Public\Documents\ArcGIS Defense Mapping\Product Files\ReferenceData\MapIndex.gdb\MapIndex\JOG_Index'
z_factor = '3.28084'
use_rasters = 'USE_RASTERS'

# Making a feature layer from the Area of Interest features, and selecting a single feature based on the NRN field
arcpy.management.MakeFeatureLayer(area_of_interest, 'AOI_Index')
arcpy.management.SelectLayerByAttribute('AOI_Index', 'NEW_SELECTION', "NRN = '1501ANE1808'")

# Use the Validate Spot Heights tool to validate spot heights for AOI
arcpy.topographic.ValidateSpotHeights(in_contour_features, contour_height_field, contour_interval, in_rasters, in_spot_features, spot_height_field, 'AOI_Index', z_factor, use_rasters)

# Check In Extensions
arcpy.CheckInExtension('Foundation')

Environments

This tool does not use any geoprocessing environments.

Licensing information

  • Basic: No
  • Standard: Requires Production Mapping
  • Advanced: Requires Production Mapping

Related topics

  • An overview of the Features toolset
  • Find a geoprocessing tool

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In this topic
  1. Summary
  2. Usage
  3. Parameters
  4. Environments
  5. Licensing information