Identify null polylines
Summary :: Usage :: Parameters :: Outputs :: Warnings :: Limitations :: Code sample
Summary
Checks for null geometries for all polylines within the river network, any found are logged in the error log table.
Usage
This tool checks for null polylines. This is a row in your river network which may have other attributes but the geometry is null. Such a line does not participate in the topology of the river network and can usually be removed without affecting any processing. Null geometries can be editing artefacts or a result of some geo-processing that has collapsed the geometry to "nothing".
Any selection on the input river network is cleared and the tool checks all polylines in the river network. Any found to be null have their polyline ID written to an error log table called tblIsNull. If the table already exists then a new table name is created with a simple numeric suffix.
The tool optionally adds the error log table to the map (default) and if selected builds a standard relate between river network layer and error log table. You can use the relate to select and jump to the polyline to streamline your editing experience.
Parameters
Name |
Help |
Data type |
River Network |
The river network. For best results the network should be within a File GeoDatabase |
Feature Layer |
Add Error Log Table to Map |
If this is ticked (default) the error log table will be added to the map for your convenience if any errors were found. |
Boolean |
Build a Relate for Error Log |
If this tick box is checked then the error log table must be loaded into the map and RivEX builds a standard relate between the Error Log table and the river network layer. You can use the relate to help you jump to and review the error. |
Boolean |
Outputs
This tool creates a stand alone table named tblIsNull, if any null geometries are encountered within the river network. The table is created in the RivEX workspace folder and stored in the File GeoDatabase found in ..\RivEX_Workspace\ErrorLogs\fGDB_RivEXErrorLogs.gdb
Advice on the structure of the error log table and how it can be used is found within this section of the manual. Take note of the warning if you plan to construct a model using the error log output in subsequent processing.
Warnings
With the release of ArcGIS Pro 3.2.1 a switch control appears on parameters that accept tables\feature classes, do not interact with it! More advice here.
Limitations
All polylines in the river network are tested, if a selection existed this is cleared prior to processing.
Code sample
A minimum code example showing how to call this tool in a python script. This can be run in console or your preferred IDE. If you right click on the tool in the RivEX toolbox and select properties you can view parameter order.
import arcpy
# Import RivEX toolbox
arcpy.ImportToolbox(r"C:\RivEX_ArcPro\RivEX.atbx")
try:
# Input river Feature Class
fc = r"C:\Temp\ORN\ORN.gdb\ORN"
# Run RivEX quality control tool
res = arcpy.scrQCIsNull_RivEX(fc, False, False)
# The rivers Feature Class, a derived output
fcRivers = res.getOutput(0)
# Get error table
tblError = res.getOutput(1)
# Check if error table exists
if arcpy.Exists(tblError):
# Count number of rows
res = arcpy.GetCount_management(tblError)
n = int(res.getOutput(0))
if n > 0:
print(str(n) + " error(s) were recorded")
else:
print("No error table created!")
except arcpy.ExecuteError:
print("FAILED to quality control network")