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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Get results for each topology errors for Polyline or Points? [on hold]

When you set up a topology to build topology rules for each polyline, or points, is there a way to get the results or summary for each Line Errors? For example, when you set "Must Not Overlap", ...
3
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0answers
79 views

topology problem in the python script(arcpy)

I'm using Python 2.7 and ArcGIS 10.1. I have one topology problem in my Python script and I don't know how to fix it. I have one road and I want to select polygons with a query where intersect with my ...
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1answer
36 views

Two inner polygons touching and covered by two different outer polygons

I need to create a topology where 1 and 2 touch but don't overlap, a and b touch but don't overlap, and 1 covers a and 2 covers b. Is it possible to achieve this? I've tried various snapping ...
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0answers
24 views

pgRouting “Can't find Table”

I am using pgRouting version 2.1.0. I am using pgAdmin III. I have created a street network using Anita Graser's guide: https://anitagraser.com/2013/07/06/pgrouting-2-0-for-windows-quick-guide/ But ...
2
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0answers
27 views

not all OSM polygons downloading in QGIS

I have been trying to download all of the polygons contained within OSM for a particular extent of the city. When I do this through > Vector > OpenStreetMap > Download Data, however, many polygons ...
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0answers
27 views

qgis snaps to outside instead of boundary

I have polygon layers that I need to be covered by other polygon layers, and many of my inner layers have a vertex on the border of an outer layer or in some cases they share an edge. Both ST_Covers ...
5
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3answers
3k views

How tool to split polylines into two-part lines at vertices in ArcGIS for Desktop 10.1?

I'm using ArcGIS 10.1 SP1 at and we have a problem. There is a serious topology bug that I've mentioned in another question that is affecting our workflow. At present, Esri has stated the fix will be ...
3
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1answer
33 views

How do I export data points from topology checker into an attribute table?

I used topology checker in QGIS to find all dangles in my roads polyline shapefile. The topology checker returned about 528 dangling ends, also called errors. How do I save these points into an ...
2
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1answer
39 views

Generalizing (simplifying) polygon shapefile or feature class in ArcMap while preserving topology?

I came across How to generalize a polygon file and maintain topology in QGIS? which asks for a QGIS solution to my exact question. I'm trying to do this in ArcMap. I start with a polygon shapefile ...
26
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5answers
3k views

Generalizing polygon file while maintaining topology in QGIS?

I have a polygon Shapefile, which I need to generalize. How can I generalize the poligons and ensure that there are no topological errors like "slivers". I already tried: Vector -> Geometry Tools ...
0
votes
1answer
43 views

QGIS topo snapping not working

I am using QGIS 2.14.0 and I need to fix some topology errors. Problem is that when I move polygon node to the another node they seem to snap correctly. However, when I move that node again, in too ...
0
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0answers
23 views

How to ensure that line features are connected to other line features at a vertex

I have a dataset with many line features that are all connected to each other. I want to ensure that they are connected at a vertex on the other line and not just an edge. I figured out one way: Use ...
0
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0answers
35 views

Loading Topology Rules in ArcGIS for Desktop with Basic license

Recently I've read that it's impossible to create topology rules below Standard License Level, BUT that one can load and use those rules (created in Standard e.g.) on a Basic License. How exactly does ...
1
vote
1answer
447 views

How to interact with GRASS GIS vector map topology “level/layers” from terminal/command line?

Is there anybody out there that can maybe assist in the most simplest form of code to call on command line to "export topology" (which is level 2 information in GRASS) as separate spatial data, as ...
1
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1answer
51 views

Does QGIS have an autocomplete polygon option like the one in ArcGIS?

I am trying to do digitizing in QGIS, but I do not see an option that I have seen in ArcGIS - autocomplete polygon. I would like to make two adjacent polygons topologically correct, and can not find ...
1
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0answers
31 views

ogr2ogr (or other) simplification of polygons with shared boundaries

I am trying to simplify a collection of 100,000 or so polygons containing nearly 4 million vertices. The data is stored in a 2GB shapefile so there is no explicit representation of the topology ...
0
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0answers
25 views

modelbuilder, combining models, output dataset type

I am combining two models and for some reason the output dataset from first model is not being accepted as input in the second model. Here is the screenshot of the first model (just last part of it): ...
0
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2answers
302 views

Automatically apply topology rule to only selected portions of a .shp file?

I am looking for some examples/tutorials on how to apply a topology rule to only a selected portion of a shp file using a script in ArcGIS/GRASS. Using ArcGIS seems to always require an interactive ...
1
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1answer
137 views

Finding Topology Errors toolbox or extension?

I do not remember if I add this Topology Errors extension or toolbox to my ArcMap. I would like to know more about this toolbox. This is not the same as the Topology toolbox that comes with the ...
2
votes
1answer
69 views

ITopologicalOperator::Simplify not removing self-overlaps

I maintain an application whose main job it is to take esri-ish things from users and turn them into sql spatial objects in our database (2008 R2). Below is an excerpt that may be useful: public ...
0
votes
2answers
260 views

Snapping polygons while reshaping edges?

I have two Polygons, A and B, in two shapefiles. Is there any automatic way to reshape the edge of Polygon A according to the edge of Polygon B?
2
votes
0answers
30 views

How to run QGIS plugin from python script

I would like to access external QGIS plugins through a python script. I have been able to access the built in QGIS processing and vector toolbox, but have been unsuccessful with external plugins such ...
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0answers
51 views

Does QGIS support topological editing of lines?

Does QGIS support topological editing of shared vertices between two or more lines? When in editing mode, if I select a vertex at an intersection, it seems that sometimes it will move all lines ...
1
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2answers
618 views
8
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0answers
221 views

Joining layers with respective elements with PostGIS Topology

I'm currently using PostGIS topology extension, but I have some difficulties in understanding how the structure works: One of the key points is the use of "layer"s: as of what I understand, features ...
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0answers
19 views

Remove inner border and extend dangles to outer border

I'm struggling with a massive file of grids that need borders extend or snapped onto the outer border of the file. I'm looking to batch this process as I'm currently using topology and and tracing ...
1
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0answers
19 views

How to use the TopoViewer in the QGIS DB Manager?

I'm just wondering what the TopoViewer in QGIS is doing. DB Manager (PostGIS) says 'Schema "schemaname" is not registered in topology.topology'. Unfortunately there is no help available and I can't ...
2
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4answers
2k views

Creating polygon of gaps/holes from several shapefiles using ArcGIS Desktop?

How can I create polygon of gaps/holes if I have several shapefiles. Do I really have to merge all layers, it it big amount of data (NEW YORK roadbed, buildings, water,parks etc) I have ET geowizards ...
0
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2answers
49 views

Administrative boundaries topology rules

I have administrative boundaries at 4 levels, each one is a feature class in a file geodatabse. Each level should be a split of the layer above. In other words one polygon from level 2 should be ...
2
votes
2answers
825 views

Topological relationship between two polygon feature layers in VBA and ArcObjects? [closed]

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 ...
1
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1answer
58 views

Geodatabase topology and geometric network on the same data

I know that I can't have a topology and geometric network on the same data in the same dataset in ArcSDE. But is there any solution how to do this? I need geometric network for generating diagrams via ...
2
votes
0answers
35 views

TopoGeometry commands with postgres are really slow

After messing around quite a while, I was finally able to get a topogeometry converted from my geometry table following the example of toTopoGeom. I have the topology extension, with a topology schema ...
4
votes
1answer
48 views

Edit polygon borders in QGIS preserving topological correctness (planar partition)

Given a layer of polygons that is topologically perfect, i.e., has no overlaps or gaps between the polygons, is it possible to manually edit the edges of the polygons in QGIS in a way that preserves ...
3
votes
1answer
63 views

Checking if two WGS84 lines intersect in JavaScript

I am trying to work out given two GeoJSON lines (WGS84), if they intersect (i.e. cross one another). Let me give some pseudocode to illustrate: // Providing Line 1 = lon1, lat1 and Line 2 = lon2, ...
3
votes
1answer
620 views

JTS - Java Topology Suite - Calculate radius from a given point

From point A, I want to check if a point B is within a certain radius from A. How calculate it usindo JTS? I tried this: Coordinate posicaoAtual = new Coordinate(-12.974900375893823, ...
5
votes
1answer
690 views

Road Topology Problem solution for junction

I am working with a Road Network. I have digitized the lines with AutoCAD Map 3D. Then Imported it to ArcMap. After entering all kind of database I have created Routing Dataset. But unfortunately its ...
1
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0answers
17 views

Moving feature classes between FGDB's creates unknown topology errors [closed]

I am attempting to merge together multiple large feature classes from different FDGB's into a single feature class and am getting unknown topology errors when checking for gap and overlap rules. I ...
3
votes
1answer
5k views

How to convert lines to polygons using NetTopologySuite?

I am trying to convert lines to polygons using NetTopologySuite(a C# port of Java Topology Suite JTS). I ran the sample console code succesfully and it generated two polylines. I then tried to run ...
4
votes
1answer
2k views

Intersecting two polylines using ArcObjects?

I have two polylines and would like to find the intersection(s) using ArcObjects / VB.NET. I'm using the following code: Dim topoOp As ITopologicalOperator = TryCast(pTestPoly2, ...
1
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2answers
52 views

Using ArcMap Topology to make admin boundaries match up?

I have two separate datasets ('Wards' and 'Census Output Areas'), whose boundaries don't quite match up (see below - wards in red, COAs in grey). Is there a way of automatically adjusting the Ward ...
3
votes
2answers
139 views

Simplify/generalize Polygons and keep topology of different layers PostGIS/QGIS

i have some polygons of a country, states, districts, communities and i want to simplify the geometry. i already simplified the geometry of each layer but afterwards of course it doesnt fit with the ...
6
votes
2answers
112 views

Snapping leaves small gap between features in ArcGIS for Desktop?

I'm using classic snapping in ArcGIS 10.1. At the scale (1:5,000) that I'm using to snap the edge of one rectangular feature to the edge of another rectangular feature, snapping seems to work fine. ...
4
votes
1answer
1k views

Creating adjacency matrix of topology graph of ArcMap for shortest path using ArcObjects? [closed]

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
156 views

How to remove spikes in Polygons with PostGIS

I'm trying to validate the topology of a shapefile. I managed to repair cases of overlap and gaps, but i can't resolve cases of spikes. The image shows one example of this situation. I used the ...
6
votes
4answers
2k views

What's the difference between hypsography and topography?

I've recently come across some data that has been labeled "hypsography". I looked it up and it sounds like topography. But this data source has data labeled "topography" separate from its ...
5
votes
2answers
314 views

Determining if landlocked polygons in ArcGIS Desktop?

Imagine that I have the need to determine landlocked countries. Is there a way to do it automatically? Any known implementations? The target platform on this will be ArcGIS.
10
votes
2answers
715 views

How do I describe a special relationship between connected edges?

Consider this simple situation where three edges connect at a node: I’d like to write a succinct and clear description of the relationship between A and B in such a way that differentiates it from ...
4
votes
1answer
289 views

Is there a standard st_relation_readable() function for translate DE-9IM strings?

Spatial databases, such as PostGIS, implement the DE-9IM model with function st_relate(), which returns a string with domain of {0,1,2,F}, meaning 0=point, 1=line, 2=area, and F="empty set"... See ...
5
votes
1answer
399 views

How do I save topology errors in QGIS?

I'm currently doing a project on finding blocked roads in a road network layer. I've figured that I can use the topology checker with the rule 'must not have dangles' and find them this way. But I ...
4
votes
0answers
84 views

Create polygon from lines in PostGIS

I'm trying to divide a polygon in smaller polygons from a line, but I think I can't use the st_split function. What I need is to create small polygons inside a big one, using linestring grid. I've ...