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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22 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
80 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 ...
3
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1answer
34 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 ...
0
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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 ...
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0answers
36 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
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 ...
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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
26 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
70 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
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
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 ...
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0answers
52 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 ...
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 ...
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
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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
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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
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1answer
65 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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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 ...
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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
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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 ...
3
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1answer
157 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
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 ...
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2answers
124 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 ...
0
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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 ...
2
votes
0answers
81 views

How to avoid topology errors when digitizing a road network?

I am working on a road layer project. For the snapping option I'm using the mode to vertex and segment and tolerance 5 pixels. When zooming in (to the max) I do not notice a gap. But when I use the ...
0
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0answers
41 views

Problem for Map Topology creation in ArcMap

I will create a map topology in ArcMap. My code defines the layer in my map topology but after call EditTopology Tools, a message show "No topology .... bla bla bla.." Any ideas why this would be ...
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1answer
61 views

Styles for Vector layers on QGIS

I'm trying to do some habitat suitability modelling on QGIS. I've downloaded several vector maps from Ordinance Survey (OS). So far I've found a Cartographic stylesheet for "OS VectorMap Local". This ...
6
votes
1answer
99 views

Automatic creation of polygons from Feature Class points in ArcGIS for Desktop?

I have two point feature classes, let's call them A and B. They are well-spaced and the points are non-overlapping: My objective is to create a topology using these two sets of points by connecting ...
1
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1answer
81 views

Arc-node topology data structures in Python GIS packages

I am looking at using the traditional arc-node topological data structure to make some spatial data analysis more efficient. I would like to avoid reinventing the wheel. Is there an implementation in ...
2
votes
1answer
156 views

QGIS Topology Checker Wrong

I use topology checker and add a rule that polylines must not have dangles. It find errors for all 36 polylines but I think some topologies are correct at the right side. Can you help me how can I fix ...
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0answers
47 views

How to check if a point is snapped to a line in QGIS

I have two vector classes, sg_point and sg_line. Any sg_point HAS to be snapped to a sg_line. I should not find errors if I use snapping correctly, but in case there are errors how do I check in QGIS? ...
0
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2answers
289 views

What is nontopological geometry?

I need a simple understanding of nontopological geometry. I am completely new in this area so please correct me if I am wrong. As far as I understand in topological geometry the object(say a line) ...
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0answers
53 views

ArcGIS: Is there any way to use topology on data in different feature datasets?

I am using ArcGIS 10.2 desktop on an SDE/versioned environment. We use the ESRI local government information model, except that we do not use parcel fabric. I am responsible for maintaining several ...
2
votes
1answer
370 views

How to test for 'if arcpy.exists' with RemoveFeatureClassFromTopology stand-alone script?

I have some datset topologies that i want to loop through, but I need to test for the assignment of feature classes so the scripts dont fail. (Using Win 7, ArcGIS 10.2, Python 2.7.5 and a file GDB) ...
4
votes
2answers
288 views

How can I remove the gap between two polygon boundaries in QGIS?

I have a couple of messy polygon boundaries (example data) that should share a boundary but don't: I've had a look at some suggested tools for a similar issue using ArcGIS in a separate question ...
0
votes
1answer
21 views

Territories that are not connected

I am looking for territories that are divided between two or more countries in a non-contiguous way. E.g, country A receives the western part of the territory, then country B receives a part to its ...
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0answers
102 views

Problems using GRASS tools for topology validation in QGIS

I'm working with a shapefile of Enumeration Districts (Setores Censitários) of the 2010 Brazilian Census. Enumeration Districts (ED) are smallest areas for which Brazilian Census data is available. ...
0
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0answers
193 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 ...
1
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1answer
79 views

Orphan road segments

I am working with OSM road data for a developing nation. Included in the dataset are various small networks of roads that are orphans or islands i.e. not connected to the main road network. For ...
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1answer
211 views

What's difference between Topology and Check Validity in QGIS?

I would like to know what the difference is between the Topology Checker and Check Validity tools? Is there anyone who knows of a good document or tutorial that explains functions of these tools? ...
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2answers
139 views

Topological errors after dissolve - how to avoid/get rid of?

After dissolving a layer in QGIS 2.8, I get a lot of topological errors in the new (dissolved) layer. Any suggestions as to how to get rid of these errors without manually editing each one? ...
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0answers
59 views

how to create Topology table?

i have gis database called Madar in pgadmin with postgis and pgrouting extension, all the data inside gis database already inserted by shp2postgre tool , what i really need now is how to make topology ...
2
votes
1answer
151 views

How to correct topology area boundary errors (slivers/gaps) on arcs in arcgis / arcsde

I use arcgis 10.1 (arcinfo licence) with arcsde to connect to a SQL Server database. The initial dataset has around 100k polygons (used for land registration, having a resolution that is around 1cm ...