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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50 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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33 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
19 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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38 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
43 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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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
89 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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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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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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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
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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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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1answer
59 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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1answer
45 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
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 ...
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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 ...
3
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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
33 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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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 ...
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
58 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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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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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
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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60 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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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): ...
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 ...
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
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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0answers
68 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
57 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 ...
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1answer
79 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
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0answers
54 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
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1answer
68 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
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1answer
99 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, ...
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0answers
19 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 ...
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2answers
61 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
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2answers
232 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 ...
3
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2answers
280 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 ...
4
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0answers
119 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 ...
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2answers
150 views

Tool or program to clean polygon dataset

I have a polygon dataset (shapefile, mapinfo tab file) which I would like to "clean" to be topologically correct. The polygons are assigned an ID which represents a specific class. For example ID 3 is ...
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1answer
32 views

pgrouting - topology creation with explicit node file

Learning pgrouting, I would like to build a simple public transport routing engine. Starting with a simple metro network (DC in my case, see excerpt below), I would like to combine the line ...