Thin Spot Heights (Topographic Production)

Summary

Generalizes spot heights for a given area of interest (AOI) in accordance with product specifications.

Usage

• The input features for this tool are typically outputs of the Generate Spot Heights tool. Use this tool when Generate Spot Heights generates more spot heights than necessary for cartographic purposes.

• This tool does not generate new output. It updates the input feature class by assigning values in the Invisibility Field parameter value to identify extraneous features for removal from a view. The result will be a simplified, representative collection of spot heights.

• The input must have an Invisibility field that will be updated by this tool.

• The input must have an Elevation field that accurately represents the elevation of the spot heights. This field must exist so that the tool can determine the high and low spots. The measurement unit of elevation is not required.

Parameters

Dialog

Label	Explanation	Data Type
Input Features	A point feature layer or feature class representing the spot heights for a given AOI.	Feature Layer
Area of Interest	The feature in the AOI that will be used to identify input features to process. Provide only one feature from the AOI.	Feature Layer
Elevation Field	The elevation field in the Input Features parameter value that will be used for the spot height.	Field
Invisibility Field	The field where the visibility attribute will be written.	Field
High Low Spots Field (Optional)	The field that will be used to identify the highest and lowest spots.	Field
Search Distance (Optional)	The minimum distance between spot heights. For example, if the search distance is 3,000 meters, there will be at least 3,000 meters between a chosen spot height and the next chosen spot height. The default value is 1,300 meters, as this is the optimal value for 50K sheets.	Linear Unit
Maximum Number Of Spots (Optional)	The maximum number of spot heights that will be processed.	Long
Input Contours (Optional)	The input contours that will be used to identify whether point features are in depressions or tops.	Feature Layer
Contour Code Field (Optional)	The field in the database that contains the domain value for index contour, intermediate contour, depression contour, and depression intermediate contour. It is a string value of the field, such as HQC.	Field
Depression Code Value (Optional)	The depression code values. A depression refers to an elevation completely surrounded by higher-elevation contour lines.	Long

Derived Output

Label	Explanation	Data Type
Updated Features	The input features that have been thinned based on input criteria.	Feature Layer

Python

arcpy.topographic.ThinSpotHeights(in_features, area_of_interest, elevation_field, invisibility_field, {high_low_spots}, {search_distance}, {max_spots}, {input_contours}, {contour_code_field}, {depression_code_value})

Name	Explanation	Data Type
in_features	A point feature layer or feature class representing the spot heights for a given AOI.	Feature Layer
area_of_interest	The feature in the AOI that will be used to identify input features to process. Provide only one feature from the AOI.	Feature Layer
elevation_field	The elevation field in the in_features parameter value that will be used for the spot height.	Field
invisibility_field	The field where the visibility attribute will be written.	Field
high_low_spots (Optional)	The field that will be used to identify the highest and lowest spots.	Field
search_distance (Optional)	The minimum distance between spot heights. For example, if the search distance is 3,000 meters, there will be at least 3,000 meters between a chosen spot height and the next chosen spot height. The default value is 1,300 meters, as this is the optimal value for 50K sheets.	Linear Unit
max_spots (Optional)	The maximum number of spot heights that will be processed.	Long
input_contours (Optional)	The input contours that will be used to identify whether point features are in depressions or tops.	Feature Layer
contour_code_field (Optional)	The field in the database that contains the domain value for index contour, intermediate contour, depression contour, and depression intermediate contour. It is a string value of the field, such as HQC.	Field
depression_code_value [depression_code_value,...] (Optional)	The depression code values. A depression refers to an elevation completely surrounded by higher-elevation contour lines.	Long

Derived Output

Name	Explanation	Data Type
updated_features	The input features that have been thinned based on input criteria.	Feature Layer

Code sample

ThinSpotHeights example (stand-alone script)

The following code sample uses the ThinSpotHeights function to thin the spot heights that have been created for cartographic display.

# Name: ThinSpotHeights_sample.py
# Description: This tool is thinning the spot heights that have been created for cartographic display

# Import System Modules
import arcpy
import os

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

# Setting the environment
arcpy.env.overwriteOutput = True

# Setting Local Variables
input_database =r'C:\Data\MGCP_TRD_4_4.gdb'
input_elevation_features = os.path.join(input_database, r'MGCP_Delta\ElevP')
input_contour_features = os.path.join(input_database, r'MGCP_Delta\ContourL')
index = r'C:\Data\MapIndex.gdb\MapIndex\TM50_Index'

# Making a feature layer from the Area of Interest features, and selecting a single feature based on the NRN field
arcpy.management.MakeFeatureLayer(index, 'AOI_Index')
arcpy.management.SelectLayerByAttribute('AOI_Index', 'NEW_SELECTION', "NRN = 'V795X16573'")

# Calling the Thin Spot Heights to thin the spots for cartographic display
arcpy.topographic.ThinSpotHeights(input_elevation_features, "AOI_Index", "ZVH", "IS_VISIBLE", "TXT", "1300 Meters", None, input_contour_features, "HQC", "5;6;22")

# Getting all messages, warnings, and errors from the tool run and printing the results back to the user
messages = arcpy.GetMessages(0)
warnings = arcpy.GetMessages(1)
errors = arcpy.GetMessages(2)
arcpy.AddMessage('Tool Messages: {messages}\nTool Warnings: {warnings}\nTool Errors{errors}\n')

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

Environments

This tool does not use any geoprocessing environments.

Licensing information

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