Validate Spot Heights (Topographic Production)

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 selects features in the Spot Features parameter value that don't pass the validation. Review 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 would be selected.

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

  Value	Details
  0	Valid
  1	Not highest point in top
  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.

Parameters

Dialog

Label	Explanation	Data 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 type for this field must be numeric.	Field
Contour Interval	The interval, or distance, between contour lines. The value can be any positive number.	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.	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 elevation values in the input raster are in meters but the contours are in feet, set the z-factor to 3.28084 (1 meter = 3.28084 feet).	Double

Derived Output

Label	Explanation	Data Type
Updated Spot Features	The Input Spot Features parameter value with updated attribution for spot heights.	Feature Layer

Python

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

Name	Explanation	Data 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 type for this field must be numeric.	Field
contour_interval	The interval, or distance, between contour lines. The value can be any positive number.	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.	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 elevation values in the input raster are in meters but the contours are in feet, set the z-factor to 3.28084 (1 meter = 3.28084 feet).	Double

Derived Output

Name	Explanation	Data 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'

# 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)

# 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