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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Loading Topology to Parcel Fabric gives Must Contain Features Error?

I've been working on migrating our parcels to the parcel fabric with hopes of migrating to the LGIM. I imported several CAD files, cleaned a large test area, and validated the topology (0 errors). ...
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55 views

polygon/polyline digitizing techniques for geological data

My current work involves extensive digitising of historic geology data - essentially the creation of new polygons and polylines based on overlain raster and vector layers. This is all done manually ...
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23 views

Topological Editing of Two different layers in QGIS

Is there a way to apply topological editing to move vertices between two coincident features that are not the same feature? For example, if I have a crop land polygon coincident with a soil polygon ...
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20 views

Fix all overlap errors without changing number of features

There is this set of features, they are owned lands that have been individually added as features, naturally they aren't perfectly placed I have fixed every big overlap and now only small lines ...
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36 views

How to move points in a polygons when editing/adjusting the polygon

I am using QGIS 2.14.3 and I am editing a few polygons in a layer, however in another layer I have some points (one or two points overlapping each polygon). Is there a way to move the points ...
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1answer
46 views

pgRouting problem: creating topology where segments touch

I am working my way through the example in the pgRouting manual (2.2). After running pgr_createTopology() and pgr_analyzeGraph(): pgr_test=# SELECT pgr_createTopology('edge_table',0.001); NOTICE: ...
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0answers
39 views

Overlapping despite topological editing

I am digitizing polygons from an ortophoto. In the snapping options, I enabled 'topological editing' and 'avoid intersection' of the polygon layer. I digitized some not-adjacent areas and then made a ...
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0answers
46 views

Aligning polygons in ArcGIS for Desktop?

I am using ArcGIS 10.3 for Desktop. I am working on a map that I have divided into 5 zones. I have drawn 5 polygons to represent each zone. I need to align the polygons where the edges meet. I am ...
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1answer
4k views

Ring Self-Intersections in PostGIS

This is a follow on from previous question. You will see I am a new PostGIS user. I have looked at the validity of the topology in my data and find around 1700 topology issues in the landcover (...
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0answers
12 views

QGIS - snapping points onto lines [duplicate]

I have two layers, one is point layer and other one is a line layer. I want the point features to snap on to the lines, but the points are away from the lines. Is there any way to move the points onto ...
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2answers
90 views

Count duplicates in ArcGIS, ArcMap 10.4

How can I find how many duplicates I have in my dataset (areas, lines, points) using ArcMap? With topology I can find overlapping objects, but I want to find duplicates. Are there any tools from ...
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247 views

How to add rule and add feature class to topology using arcpy and stop getting error 000732?

This script successfully added feature classes to topology when that is all I had scripted it to do. Now I've added the add rule parts (#added) and it's still just adding feature classes without ...
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1answer
22 views

How to solve “features were not reachable” warning message using v.net.distance in GRASS

I'm using GRASS 7.0.4 under Linuxmint 17.1 KDE. I need to build a raster with the shortest distance from every pixel to a city following a road. I have two shape files, the city (point) and the road (...
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2answers
285 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 ...
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0answers
37 views

Pg_dijkstra empty results

I am currently working on PgAdmin, and the pgrouting extension, in order to get the length and the path of the shortest path between every LNG terminal over the world (I have them as a table of points)...
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0answers
34 views

Removing overlap within multipart polygon in ArcGIS for Desktop?

ArcMap 10.1 SP 1 License: Advanced I am attempting to remove overlapping portions of a multipart without going through the steps exporting or creating a layer from each part and clipping individually....
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0answers
7 views

Conversion of Object ID to coordinates x y,SYSTEM: epsg:5514 - s-jtsk (Greenwich)/Krovak East North) in QGIS?

i need to get the coordinates from the shapefile - in atribute table, there are only data: OBJECTID,N,9,0 OBJECTID_1,N,9,0 (and other columns) These data represent parts of the rivers, not points ...
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1answer
25 views

Confusion with Postgis Topology and Geometrytype

in the moment I try to understand the principles of postgis topology. While testing I discovered a behavior, which I don't understand. I have a table public.test with a standard geometrycolumn type ...
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1answer
60 views

Editing with Map Topology performance in ArcGIS Pro?

I have been working on some basic cartography for a fantasy world I am creating, and ArcMap 10.4 was being slow on editing some of the large island polygons I am creating. I figured that as all I am ...
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0answers
19 views

topologically valid features from google earth

I'm currently working on QGIS and ArcGIS software for creating land use/land cover and road network map from Google earth. I traced the shared boundary between two land-use types twice since i don't ...
2
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0answers
26 views

Gas Utility Routing software in open source or algorithm [closed]

objectives : To make a web application for gas utility that can perform upstream and downstream I have googled a lot but cannot find any Gas utility routing in open source. what i have is data for ...
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0answers
49 views

Problem with polygon topology in ArcMap 10.4

I want to find errors - overlapping polygons in ArcMap 10.4. I created topology for my polygon layer (buildings) but error inspector shows me that all of my buildings are errors which is of course not ...
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0answers
28 views

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

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
89 views

topology problem in the python script(arcpy) [closed]

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
40 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 options,...
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40 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 ...
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0answers
34 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
31 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 ...
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3answers
4k 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
44 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
59 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 (...
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5answers
4k 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 ...
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1answer
62 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 ...
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0answers
24 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 ...
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0answers
39 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 ...
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1answer
484 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 ...
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1answer
68 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 ...
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0answers
61 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 ...
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0answers
29 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): ...
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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 ...
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1answer
142 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
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1answer
110 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 ...
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2answers
333 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
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0answers
40 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
71 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 ...
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2answers
635 views
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243 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
23 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 ...
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0answers
22 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 ...
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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 ...