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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92 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 ...
6
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2answers
171 views

What controls the direction of TopoGeometry Linestrings?

In PostGIS, what if anything controls the direction that topogeometry LINESTRINGs will have when converted to geometry? It doesn't appear to be the order in which the edges are listed in the call to ...
1
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1answer
42 views

start editing encountered one or more layers with error and can not continue this data is not editable

I create two feature classes by importing an already existing layers then I create a topology and I set the rule such that a point feature class must be covered by endpoints of the other line feature ...
3
votes
1answer
550 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 ...
2
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1answer
493 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, ...
0
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1answer
168 views

Delete all data from a PostGIS topology

I need to delete everything (faces, nodes, edges, anything I'm not thinking of) from a PostGIS topology, but I want to keep my database schema (schemas, tables, columns, sequences, etc.) intact. Is ...
0
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1answer
12 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
30 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. ...
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0answers
44 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
46 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
299 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 ...
0
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1answer
45 views

Select and count street pattern features (morphology) using ArcGIS for Desktop?

I'd like to be able to select and count the number of cul-de-sacs, lollipops, dead ends, or other types of street structure in a hillside community.
1
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1answer
55 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
54 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? ...
1
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0answers
29 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
39 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 ...
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0answers
67 views

Removing pseudo-nodes using QGIS Sextante plugin?

I have a road network (vector) that i'm interested in carrying out some space syntax analysis on. Predictably my GIS data is in a pretty terrible state. For example, there are a bunch of roads on the ...
1
vote
1answer
45 views

Implementing topology rule Line Feature Class should not overlap with Polygon Feature Class in ArcGIS Desktop?

Is there a way to setup such a rule in ArcMap 10 Topology that Line Feature Class features shouldn't overlap with Polygon Feature Class features?
0
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1answer
43 views

Enabling: Raster and Topology

I'm new to GIS and tile servers. I've installed TinyOWS pretty successfully except for what looks like to be some dependency issues. I have installed PostGIS and also PostgreSQL. PostGIS is supposed ...
2
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2answers
47 views

QGIS Editing: move - both - nodes after Cut has been performed

I just ran into unexpected behavior while editing a polygon shapefile in QGIS 2.8.2. Scenario: A polygon: Then I cut that polygon into two seperate poygons: Then I use the Node Tool to move a ...
2
votes
1answer
125 views

Identifying “Must not connect point more than one line feature” errors in electrical network?

I have attached an example image to show the problem: This is electrical network data single service point to connect more than one Service pole. Is it available any topology rules? I would like ...
0
votes
1answer
27 views

PostGIS Topology Requires Admin

I am running PostGIS on an Ubuntu server. I am able to add the Topology extension via CREATE EXTENSION, but when I try to use it as anything other than an admin I am denied permission. I ran GRANT ...
0
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1answer
22 views

Double Entries/ Errors with Digitizing Polygons

I have a layer that has errors, i mean polygons have double entries (digitized twice), i can edit manually but there's a lot of attributes and it will take ages to clean the data. Is there any short ...
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1answer
40 views

Parsing path and calculate value in model builder

I am experiencing an issue with the model only tool calculate value. I am attempting to use the parse path and calculate value model only tools to force a feature dataset into the create topology ...
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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?
0
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0answers
44 views

Invalid Topology/Topoengine error: Intersect and Clip

I have a large, provincial extent gdb file with numerous detailed polygons (representing roads, buildings, forest cover, etc), and want to clip this layer to about 700 unique polygons, some of which ...
0
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1answer
39 views

Delete Features from a feature class that participates in a topology

I have an enterprise geodatabase and I would like to delete features using the tool from a feature class that resides in one of the feature datasets and participates in a topology. I tried using the ...
4
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2answers
1k views

How can I identify gaps in polylines and polylines with more than one end point using ArcGIS 10?

I have a multipart polyline shapefile containing a large number of lines, some of which are broken by gaps and some of which have more than one start and end (by mistake - see attached). I need to ...
2
votes
1answer
926 views

File Geodatabase XY Resolution and XY Tolerance

Here - http://gisintelligence.wordpress.com/2011/04/19/limiting-xyz-geometry-drift/ I found the description of XY Resolution and XY Tolerance in "Arcgis World". I have a question - my cadastral data ...
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2answers
850 views

Dissolve polygons - group to others with touching corners

I am working with some data that shows land management. There are many places where corners "touch". I would like to dissolve my dataset so that features are grouped (dissolved) with those that they ...
3
votes
1answer
54 views

Prevent PostGIS Topology from splitting edges on line insert

I'm dealing with a large amount of road data represented with PostGIS Topology types. Anytime I add an edge over another edge, the edge is automatically split and a new node is created at the ...
3
votes
2answers
363 views

How do you remove isolated roads from a bigger network?

I'm trying to perform an OD Cost Matrix calculation on a set of points using a road network from OpenStreetMap data. The network contains lots of roads that don't connect to the rest of the network. ...
2
votes
1answer
75 views

Enforce topology rule over a shapefile

I have a couple of shapefiles, the first one is a set of points, while the second one is a set of lines. I need to regularize the shapefiles in order to be able to generate a graph (adjacency list / ...
5
votes
3answers
1k 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 ...
0
votes
1answer
34 views

TopologyException error during fortify SpatialPolygonsDataFrame

I tried to reproduce a recent question on spatial data visualization using ggplot2 and received the following error message during fortify(world, region = "ISO3"): Error: TopologyException: Input ...
7
votes
3answers
9k views

Analyzing differences between two shapefiles to put results into new shapefile?

I have two polygon shapefiles of the same region from two different years (1985 and 1997) and I need to analyse the differences between the two shapefiles resulting in a third polygon shapefile ...
10
votes
7answers
2k views

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 ...
0
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0answers
36 views

QGIS topology overlap check

I have checked topology rule must not overlap with and i get error The problem is that i have check this many times, and made hole vertex after vertex so it is not possible that these objects ...
1
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0answers
59 views

Topology in Arcgis and QGIS

I have been studying topological methods like 4 intersection , 9 intersection, dimension extended and CBM (calculus based methods) like RCC-8. I want to know which of this method is used for ...
1
vote
1answer
35 views

Setting junction properties in ArcGIS Desktop?

I have a situation where I have a line feature class and need to build a network out of it. The lines represent roads. I wonder how I can model the intersections on the network. Almost all of them ...
2
votes
2answers
75 views

List File Geodatabase Topology

I'm trying to write a script that looks into a dataset and list all the elements in the dataset. The dataset comprises of Feature classes and FGDB Toppology. When I uses ListFeatureClasses, it outputs ...
0
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0answers
38 views

How to identify Topology Exception

Anyone have any innovative way(s) of "quickly" marking topology exceptions. I have ~300,000 bridges which have pseudo nodes located on either side of the bridges where the bridge and road endnotes ...
0
votes
0answers
189 views

Grass Processing tools via QGIS : v.clean snap, chdangle, and rmdangle

Using QGIS 2.6 Grass Processing tools, I'm trying to clean up topology on a water network layer. I noticed topological errors when first trying to break all lines on intersections using v.clean break. ...
9
votes
1answer
175 views

What PostGIS [topology] provided tools may be used for data quality assurance?

I'm learning about techniques to ensure GIS data quality. Googling around, I've found a few papers about theory and best practices (here and here), and a couple of short presentations about the topic ...
0
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2answers
64 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?
5
votes
2answers
6k views

How to repair topology of a shapefile?

I performed an object-based image analysis using ENVI EX, and each of the classified features were exported as a shapefile. I transferred those shapefiles into ArcMap 10, and tried to intersect them ...
2
votes
1answer
67 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. ...
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 ...
0
votes
1answer
73 views

Geometric Network Build Error

I'm trying to create a geometric network of pipes, sewer structures (points) and manholes (points) inside a of an SDE. I can create the network in a file geodatabase but when I try creating it inside ...
0
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1answer
55 views

Using multi-part line features in network analysis?

Cartographically is there any reason why (pro / con) multi-part line features should not be used when developing road networks for ArcGIS Network Analyst? For example, say I have a road which is 100 ...