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Topology error ArcGIS

In 2012 an ArcMap user wrote Automatically fixing multiple errors using Fix topology error tool?:

I am a ArcGIS.10. user. I'm want to solve multiple errors using the fix topology error. So I select all my features I click right but I don't have the correcting options [Snap, trim, extent], I only have Delete. Does anyone know why?

Now I have about the same problem with overlapping line features which I would like to correct with subtract without the need to select and subtract each single error.

Is there in 2018 the option to correct all errors in one go?

For overlapping line features there is only the option to subtract, but still when I select multiple errors the option to use subtract is greyed out.

Currently I have more than 10000 errors in a big data set of an indoor environment.

This image shows an administrative unit polygon file, where a new topology was created to produce the layer shown in red outline. The map shows the extra lines in red inside the external boundary [in this case the international boundary], these represent the topological errors.

Using ArcGIS to check topology

Create Empty Geodatabase

In ArcCatalog, go to the folder where you want to save the geodatabase.
Right click in open space and choose New > Personal Geodatabase
Name the geodatabase ISO3_update_yymmdd.mdb [e.g. usa_update_070801.mdb]

Create Feature Dataset

Right click on the geodatabase and choose New > Feature Dataset
Name the dataset ISO_topology [e.g. usa_topology]. Click Next.
Select the Geographic Coordinate System > World > WGS 1984. Click Next
For the vertical coordinate systems, leave as . Click Next. Click Finish

Import Layer to Feature Dataset

Right click on the feature dataset and choose Import > Feature class [single]…
Specify the following:

Input Features: The path to the data under check
Output Location: The empty feature dataset created in section 2 above
Output Feature Class: Name the feature class ISO3_work_yymmdd

Create Topology

Right click on the feature dataset [ISO3_topology] and choose New > Topology…
Click Next.
Accept the default name [ISO3_topology_Topology] by clicking Next
Select the feature that will participate in the topology and Click Next
Click Next
Click Add Rule…
Select Rule > Must Not Overlap and Click OK
Leave Show Errors checked
Click Add Rule…
Select Rule > Must Not Have Gaps and Click OK
Leave Show Errors checked
Click Next
Click Finish
Click Yes to validate the topology

Visualize Errors of the Topology

Click on ISO3_topology_Topology and the Preview tab
If the preview of ISO3_topology_Topology shows only one red line that follows the outline of the main polygon, the file is free of topological errors.
If the file has topological errors, it will have multiple lines; one associated with the main polygon, and the others associated with the locations of the gaps and/or overlaps in the data [see Figure 4].

TIP: If the dataset has very poor topology, feature coordinates may collapse when you validate the topology, even with a low cluster tolerance. To prevent this, go to Data Management Tools > Features > Repair Geometry and repair the geometry BEFORE creating the topology.

One of the most common problems in data quality is the presence of gaps or overlaps in polygons such as administrative boundaries. Detailed technical guidance for editing data topology in ArcGIS is below.

Set up the editing environment

Open ArcMap

Import into ArcMap ISO3_topology_Topology [created in Quality Check on page 11]
Click on Yes to add feature classes that participate in topology

Set the Editing Parameters – In order to perform the editing procedures, it is important to set the editing parameters as follows:

Change map Units

Go to View > Data Frame Properties
Click on the General Tab
Change Units – Display: to Meters
Click Apply > Okay

Set up the parameters

If it’s not already there, add the Editor toolbar to your workspace by going to View > Toolbars > Editor
On the toolbar, go to Editor > Options
Under the General Tab chose Snapping Tolerance: 50 map units
Under the General Tab choose Sticky Move Tolerance: 1000 map pixels [This will prevent accidental moves of polygons during the editing process.]
Click OK

Start the Editing Process

Start Editing

Click on Editor > Start Editing
Select the Task: Modify Feature and the Target: ISO3_work_yymmdd

Set Snapping Parameter

Go to Editor > Snapping
For the ISO3_work_yymmdd layer, check the boxes for Vertex and Edge
If toolbar not already opened, add Topology Tools
Go to Editor > More Editing Tools > Topology [another toolbar will be added]

Shows ISO3_topology_topology in red and ISO3_work_yymmdd in blue

Repair Overlap Errors

Select Map Topology from toolbar > Select ISO3_work_yymmdd > Click OK
Go to Topology toolbar > Click on and Select ISO3_topology_Topology
Select all Overlap Errors using the Error Inspector tool > Show ISO3_work_yymmdd – Must Not Overlap > Click on Search Now
Select all the errors
Correct the selected Overlap Errors using the Fix Topology Error tool > Right click on the map and choose Subtract
Verify there is no more error with the Error Inspector tool [by repeating the Search Now command as above]
Go to Editor > Save Edits

Repair Gap Errors [limited to one polygon at a time]

Zoom to error
Using the Fix Topology Error tool [], select all the topological errors associated with one of the polygons > Right Click > Select Create Feature [see Figure 7]
Figure 7 - Shows the topological errors selected from ISO3_topology_topology in black
Select the polygon and the new polygons created using the Edit Tool [] or open the attribute table and highlight the main polygon and the newly created polygons [they will be at the bottom of the table and have null values].
Go to Editor > Merge to merge the selected polygons. Select the main polygon as the feature with which polygon will be merged [to keep the Attributed Table information] > Click OK.
Save Edits
Continue for all errors

Fix Your Editing Errors with this ArcGIS Topology Tutorial

Unless you’re a data editing Jedi, your GIS data may unknowingly have errors like gaps and overlaps… What to do? Use topology rules in ArcGIS:

If you answer yes to any of the following questions, you should consider using GIS topology rules to check to validate and fix errors in your GIS data.

Do unwanted gaps exist in your data?
Do overlaps exist?
Should lines touch the boundary of polygons?

TOPOLOGY is a set of rules on how points, lines, and polygons share their geometry. Topology validates the spatial relationship between neighboring and overlapping features.

Types of Errors: Accuracy vs Precision

Analysts often assess data validity using accuracy and precision – which aren’t the same. What’s the difference between “accuracy” and “precision”?

PRECISION identifies the closeness of two or more measurements to each other. ACCURACY refers to the closeness of a measured value to a known value.

Unknowingly, errors can exist in GIS data. You may not even know. How scary is that?

That’s why we can fix errors automatically with topology rules. For example, positional accuracy, digitizing error, data generalization, and age of data are often sources of data error.

Also, when you have two conflicting data sets, conflation [edgematching and rubbersheeting] resolves conflicts by preserving the most accurate one.

Esri Topology Rules in ArcGIS 10

Topology rules ensure connectivity between GIS datasets. It fills in gaps, removes slivers, and fixes overlapping polygons. When polygons share a boundary, topology rules enforce data integrity.

…But you already know that.

Let’s get into the nuts and bolts of how to use topology in ArcGIS.

Step 1: Add your data to a geodatabase

Creating topology rules in ArcGIS is just a couple of simple steps. First, add your data in a feature data set.

Step 2: Create topology data set

Once your data is in a geodatabase, you have to create a topology data set.

Follow the instructions by selecting your feature class.

Step 3: Add topology rules

There are over 30 rules you can add to inspect the quality of your data. One by one, you add rules which govern exactly how to perform quality control to your spatial data. Below is a screenshot of adding an overlap rule.

Overlapping polygons can be resolved by the topology rule “must not overlap”.

Select yes to validate. This is how ArcGIS refreshes and ensures that it’s using the most recent data errors. The geodatabase should have a topology dataset within it now:

Step 4: Inspect your data

Once your data is in a geodatabase and rules have been added, you can now inspect your data topology. ArcGIS topology fixing is interactive. One by one, you can go through errors and fix them with the error inspector.

Click the Add Data button

Add the topology data set.

The errors in your data will appear as area, line, and point errors.

Step 5: Correct your errors

The ArcGIS topology tools support richer, complex error checks. Resolve topology issues with automatic or manual fixes.

Add the Topology Toolbar by clicking Customize > Toolbars > Topology. If the Topology Toolbar is greyed out, you have to turn on Editing mode by clicking Editor > Start Editing.

When you push the error inspector button, you can manually go through each error.

Going through the error inspector report, you can right-click individual errors for quick fixes. Here are the types of topology fixes you can perform:

MERGING: The overlapping portion will be subtracted from one polygon and added to the other polygon.
SUBTRACT: The overlapping portion will be removed completely from both polygons.
CREATE FEATURE: The overlapping portion will be removed completely from both polygons and added as an entirely new feature.

Preventing Errors by Using the Snapping Environment

Using snapping in GIS can prevent errors from happening altogether. The snapping environment determines the distance that newly digitized points, lines, and polygons will occupy the same location as existing features.

When new features are created in the editor, they will be automatically snapped to existing features. For example, you can snap to edges, points, ends, intersections, midpoints, and tangents.

What’s Next?

When errors exist, topology tools clean geometry for GIS features.

Topology is especially useful for detecting and correcting errors of digitized data because it checks and validates the spatial relationship of neighboring and overlapping features.

Topology editing is a strong point in ArcGIS with a ton of options to fix editing errors.

It’s really the best of its kind.

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