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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208 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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35 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 ...
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1answer
24 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 ...
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2answers
132 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 ...
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2answers
55 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 ...
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28 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 ...
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0answers
27 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
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1answer
167 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 ...
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2answers
44 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?
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2answers
5k 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 ...
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1answer
41 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. ...
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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 ...
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1answer
40 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 ...
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1answer
30 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.
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1answer
35 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 ...
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3answers
149 views

Automatically add vertex to polygon where vertex of another polygon touches it?

The polygons that I use in ArcMap 10.2 are drawn so that they snap to each other, but never overlap. I've described a general case in the following image: A polygon is defined by the minimum ...
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1answer
56 views

How to suppress polygon boundaries shared by objects of same type in QGIS?

Given polygons - like landcover in OpenStreetMap or street areas in cadastre - how can one suppress those polygon boundaries which are shared by objects (features) of same type in QGIS (see figure ...
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0answers
34 views

ArcGIS planarize vs autofixing “must not intersect or touch interior” topology

trying to fix topology errors in OSM here. I am wondering whether ArcGIS planarize is essentially the same as creating a topology that says a class must not intersect or touch interior. Then ...
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3answers
305 views

X,Y Tolerance vs. Cluster Tolerance

I can set a "X,Y tolerance" or use default when I create a new feature class. I can set a "X,Y tolerance" or use default when I create a new feature dataset. I can set a "Cluster tolerance" or use ...
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1answer
37 views

Simplifying polygons in ArcGIS considering contains-one-point topology rule?

I want to simplify polygons using the "Simplify Polygon (Cartography)" tool in ArcGIS 10.2. Additionaly there is one point in each polygon and this condition should still be fulfilled after ...
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1answer
58 views

Is there any topology handler in QGIS?

When importing autocad maps, sometimes topology will be chaos, this need to be amended. And when I add new topology in QGIS, how to save that to the postgreSQL? Is these functions included in QGIS or ...
2
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1answer
72 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 ...
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0answers
48 views

Metric maps vs topological maps for path finding and UI rendering of indoor floor layouts

I'm building a software to map indoor floor plans of large facilities (like malls). I read through some of the questions on this forum, but my constraints are a little different than the ones ...
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0answers
50 views

Polygon Layer Cleaning with QGIS

I have a little situation with my data. I have vectorized a raster layer, and now I have some issues with the geometries, as you can see in the picture. Most of errors I have are like this one. ...
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1answer
67 views

How to connect lines with gaps to continuous line?

and I have a lot of this problem like in image. The two line are separated but i want a continuous line. What rule should I choose in Topology Checker? I want to know all the separated line, so i can ...
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1answer
81 views

Polygon intersection with LineString in PostGis

I have a table which contains GPS coordinates at certain times. I created a LINESTRING from them ordered from the oldest to newest. I also have a POLYGON and I would like to determine the subset of ...
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2answers
305 views

Getting line FID from polygon ITopologyGraph

I want to export polygon Arc list to txt file for that I created topologygraph for personal geodatabase feature class (polygon) using ITopologyGraph::build. I got polygon FIDs but I am not getting ...
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2answers
38 views

Splitting polgons in QGIS produces topology errors

I am trying to split existing polygons but when I do, gaps and overlaps are created between the polygon I am cutting and adjacent polygons. I have snapping switched on and have enabled topological ...
2
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2answers
631 views

Why does Erase give ERROR 999999 (Error executing function Invalid Topology Negative point valence)?

I am getting the following error when I try to erase a set of data from a file within a gdb. Any idea on what to do? I have done repair geometry multiple times on the input/erase datasets. I have 16GB ...
2
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1answer
46 views

Editing polygons simultaneously in ArcMap?

I have two polygons: How can I reshape both Polygon 1 and Polygon 2 at the same time? Will the area of each polygon change automatically in the table after reshaping? I'm using ArcMap 10.1.
2
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1answer
31 views

Topology Editing using ArcView (now called Basic) license level of ArcGIS Desktop?

I am building a geodatabase from data collected on a GPS handheld in the field. The GPS device collects decently accurate information but I need to make sure all the polygons, lines, and points are ...
2
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1answer
3k 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 ...
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8answers
2k views

How to build topology without Standard/ArcEditor or Advanced/ArcInfo license?

I have a huge dataset that I am capturing that was full of errors previously and I want to make sure that the new version is error free - which can be very time consuming with only a Basic/ArcView ...
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3answers
2k views

Create features from ArcGIS Topology errors

I have imported field users shapefiles into an ESRI geodatabase so that I can create some topology rulesets that identifies the errors as needed. Unfortunately the field users do not have a license ...
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2answers
463 views

Topology Edit Tool in ArcGIS Engine

Is a Topology Edit Tool available "out of the box" for ArcGIS Engine 10? Or do I have to write one myself?
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2answers
362 views

Just view topology errors in ArcGIS

I have a basemap (parcels), which is to be used as target for several conflation tasks. This basemap MUST NOT be modified in any way. The basemap ist part of numerous topology rules. Each time ...
2
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2answers
68 views

What is the difference between Intersect & Overlap in ArcGIS Server?

When you run a Query Task on the ArcGIS Server's REST Endpoint, you need to give a spatialRel There are two spatial relationships which are quite similar: esriSpatialRelIntersects & ...
2
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1answer
256 views

What am I doing wrong with QGIS v.clean?

I thought I understood how the GRASS v.clean tool worked in QGIS (in 2.6.1 Brighton) but I keep getting unexpected results and errors with a polygon ShapeFile. I've run the QGIS TopologyChecker with ...
7
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1answer
449 views

Algorithm to fill the gaps adjacent to parcels

I would like to find a way to fill the gaps between the road and its surrounding parcels, like described in picture below: I have different parcels like A and B , i want to fill the gaps by adding ...
7
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1answer
165 views

Suitable algorithms for simplifying isochrone polygons

I'm looking for an algorithm for simplifying isochrones which were generated using OSM data. These are generally characterised as having lots of small "holes" mostly due to missing OSM data but also ...
24
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5answers
2k views

How to generalize a polygon file and maintain 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 ...
3
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0answers
67 views

How to simplify polygon shapefile and maintain topology? [duplicate]

I'm looking for a straightforward answer that actually works...not a 'duplicate question' flag. None of the other solutions posted in similar threads actually work...they all have dead-end answers ...
2
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1answer
50 views

ArcMap remove feature-class from feature-dataset

I am using ArcMap 10.0 (Editor). I have got a feature-dataset within a GDB with several feature-classes and an topology. I am unable to find a way to delete/remove a feature class from that ...
0
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0answers
43 views

Any way to speed up my postgis topology creation?

I need to do topology aware simplification, and I'm investigating PostGIS's new topology extension. However it's taking a very long time to create the topology, and I'd like to know if there's ...
0
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0answers
42 views

How to eliminate sliver polygons with QGIS [duplicate]

I need to remove sliver polygons within a shape, but using QGIS 2.6 generates some failures to the process. I mean the program freezes or shuts down and I don't know why. Maybe there's a bug or it ...
1
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0answers
64 views

QGIS Topology checker wrong results?

I am trying to understand topology checker results and frankly i dont get it - probably i am doing something wrong. Source - Point layer Target - Polygon layer Must be inside - that is working as ...
0
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1answer
56 views

Grass GIS “v.in.ogr”: How to prevent crossing lines from beeing split where they don't share a common node?

I want to import a road network into grass gis to run network analyses. I use "v.in.ogr" to import my road shapefile. The problem is that Grass GIS seems to split every crossing line no matter if they ...
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0answers
210 views

Intersection postgis TopologyException

I'm trying to make a quite simple analysis in Postgis, but I'm finding some problems. I want to in the first place create buffers for then, intersects themselves but one, this will be differenced. ...
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25 views

GRASS: How to remove several categories from a geometry?

I am totally new to GRASS (and have found it difficult to get into that way of thinking and its terminology). I use grass70 under Ubuntu 14.04. I have the following problem which I have tried to ...
3
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0answers
37 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 ...