I’m working with two separate line layers in ArcMap. One represents an original dataset, and the other is an updated version. In some places, the lines from both layers follow the same path and overlap exactly, but in other areas the updated layer diverges and does not match the original.
I need to identify and extract only those portions of the updated layer that do not overlap, touch, or share any line segments with the original layer. This will enable me to distinguish between “new” geometry and “existing” geometry.
My ArcMap license level does not include the Detect Feature Changes tool, so I’m looking for an alternative method or workflow to accomplish this using tools available in my current license.
My question:
What is the best workflow or tool in ArcMap to extract only the parts of one line layer that do not overlap or coincide with another line layer?
well with arcgis pro and an advanced license, you would want
Symmetrical Difference (Analysis)—ArcGIS Pro | Documentation
which you could emulate using the basic difference tools and various spatial filtering
Thanks for the suggestion. Unfortunately, my ArcMap license is Basic, and I don’t have access to ArcGIS Pro at my workplace, so I can’t use the Symmetrical Difference tool directly. I’m looking for an alternative workflow that can achieve a similar result using the tools available in ArcMap Basic
Symmetrical Difference would keep parts from both lines which do not Overlap. I think you only want non-overlapping segments from one feature, is that right?
You have to be very precise with your terminology here as a line can be made of many segments. A segment could overlap or be coincident to the other feature at some point, but not entirely overlap.
It might be handy to produce a graphic of your input and sketch of your intended output.
however I think you just want to Erase Erase (Analysis)—ArcGIS Pro | Documentation one feature from the other, is that right? Advanced license again but workarounds can likely be done.
Depending on your needs, one option might be to Select features using the Select By Location tool, then click the Switch selection button in the attribute table.
That wouldn't account for partial overlaps of segments.
If I understand what you're intending correctly, and you also only have the Basic license:
Pairwise Erase (Analysis)—ArcGIS Pro | Documentation
Hello EHSANAZHARI,
This probably doesnt help. What I have been doing in ArcMap, and now in ArcPro, to determine what has changed within each featureclass within each featuredatabase, I have created a "admindate" field in each featureclass. Using ArcPy, I can then query out all features within all featuredatabases that have changed or been added post the admindate or change date = NULL. Change Date = null upon adding. All the queried features are put into a featureclass within a database. I then sequentially go thru the featureclass to update the master GIS. Once the master GIS is updated, I change the "admindate" to the what ever the current date is (also thru ArcPy). Assumption, tracking is turned on where the change date are internally updated.
Back to your question. Is there a field with a unique Id that is common to the line layers. If so, maybe you could join the table to the master line layer. Everything that joins where the edited dates are different, are those features that do not share the same geometry. Any features that don't join, or those features that were added.
I hope that helps
~Jeff