Topology describes non-metric relationships among geometric figures, such as adjacency, containment, and orientation. It is a branch of Mathematics, which deals in geometry without measurement.

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How to identify polygons with “flag” sliver errors

Working in ArcMap, I have come across errors in a polygon layer that I will call "flag slivers" (taken from similar language in parcels call "flag lots"). These sliver polygons (see image below) are ...
7
votes
3answers
2k views

Create features from ArcGIS Topology errors

I have imported field users shapefiles into an ESRI geodatabase so that I can create some topology rulesets that identifies the errors as needed. Unfortunately the field users do not have a license ...
7
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2answers
831 views

What does 'building topology' mean for pgRouting?

From a couple of answers at gis.stackexchange.com and at the pgRouting mailing list I have found out that pgRouting 'builds topology'. What does that mean? If for example we import an .osm file into ...
9
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2answers
1k views

How to preserve topology while editing polygons in OpenLayers?

I’m facing this issue: I have a chloropleth map based on a set of polygons with some data. Using WFS-T (postgis, geoserver, openlayers) I am able to edit the geometry of the polygons. This works fine. ...
5
votes
2answers
374 views

Just view topology errors in ArcGIS

I have a basemap (parcels), which is to be used as target for several conflation tasks. This basemap MUST NOT be modified in any way. The basemap ist part of numerous topology rules. Each time ...
7
votes
1answer
228 views

Optimize GEOSGeometry's spatial operations by avoiding thread-safety checks

A ranking algorithm I'm developing for a Django webapp requires performing spatial operations (within, intersections, sym_difference, etc.) using a query against large number of geometry objects. ...
2
votes
3answers
1k views

Batch fix overlap errors

I have a feature class with about 250,000 contiguous polygons. ArcEditor turns up around 9,000 overlap errors when I validate the topology. I want to merge each of these errors into one of the ...
2
votes
2answers
757 views

Topological relationship between two polygon feature layers

I have two polygon feature layers: one representing land parcels and one representing roads. Some land parcels (polygons) coincide with a part of a road (another polygon feature). How can I check ...
6
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1answer
98 views

Dividing the world space to geographic sub-space

I am trying to divide the world space to geographic sub-space from "general" to "specific" locations and without using latitude and longitude information. That is, I am trying to think about the world ...
-1
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2answers
629 views

topology problem

Can anyone tell me how to fix an error after running the topology rule in ArcGIS? I tried to subtract and create a new layer, but a failed warning appears every time.
4
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2answers
467 views

Topology Edit Tool in ArcGIS Engine

Is a Topology Edit Tool available "out of the box" for ArcGIS Engine 10? Or do I have to write one myself?
1
vote
0answers
271 views

topology rules for structuring topology data to get line feature as topoparent in topology graph

i Created topology graph of a polygon feature and i copied geometry of topology edges into line feature class,and topology nodes into point feature class i created topology layer containing ...
5
votes
1answer
1k views

How to create adjacency matrix of topology graph of arc map for shortest path?

I have created a topology graph of a polygon feature and I want to find the individual FIDS of the lines of the polygon. I want to construct an adjacency matrix to create the shortest path. How can I ...
3
votes
1answer
744 views

3d polylines and polygons

Is there a way to extract z values from a DEM into a polyline and/or polygon featurclass in arcmap 10? I would like to have 3d polylines and polygons to make cross sections in a CAD, but currently I ...
3
votes
2answers
309 views

Getting line FID from polygon ITopologyGraph

I want to export polygon Arc list to txt file for that I created topologygraph for personal geodatabase feature class (polygon) using ITopologyGraph::build. I got polygon FIDs but I am not getting ...
1
vote
2answers
337 views

topology of geometries in gis

http://imm.io/2cpJ What is the thinking of OGC to keep this point that "point have no boundry , it just has interior"... what do they mean? this notation: F**F*****...still i am confused due to OGC ...
20
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2answers
2k views

What are the benefits of Multipart Features?

Multipart points, lines, and polygons are implemented in nearly every GIS, but what benefits, if any, do they provide? In a relational database attributes shared by different features can be stored ...
12
votes
4answers
3k views

Remove Duplicate Polygons Using Open Source Tools

I have a shapefile containing features with duplicate geometries, but different attributes (e.g. a polygon with attribute XX, and an identical polygon with attribute XY). I want to identify the ...
3
votes
1answer
776 views

Converting ArcGIS topology rules file (*.rul) to *.txt, *.csv or *.xls for reviewing?

Has anyone converted ESRI's topology rules file (.rul) into another format? I built a complex topology rules set and would like to QC it in something easier to read and work with than ArcCatalog. ...
1
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2answers
1k views

Arc node topology in ArcMap

I would like to implement an arc node topology in arcmap. Do you know how can i build node topology from line layer in ArcMap 9.3.1?
9
votes
5answers
1k views

How to convert line simple features to topological network?

using Gdal/ OGR is there a way to convert a shp, kml, or PostGIS line layer into a network of nodes and segments so it can be used in packages such as networkx?
9
votes
8answers
2k views

How to build topology without Standard/ArcEditor or Advanced/ArcInfo license?

I have a huge dataset that I am capturing that was full of errors previously and I want to make sure that the new version is error free - which can be very time consuming with only a Basic/ArcView ...