Questions tagged [adjacency]
Spatial relationship where two features share a common border under some interpretation - ie, are 'next to' each other.
3
votes
0answers
45 views
Grouping polygon neighbors recursively using PyQGIS? [closed]
I have a shapefile with polygons and need to group them with the same Group_ID if they touch each others. The thing is, once I start assigning a number to one polygon, it needs to keep looking for ...
2
votes
1answer
43 views
Ordering polygon neighbors in clockwise order using ArcMap?
In ArcMap, I am using the Polygon Neighbors tool to generate a list of each polygon's adjacent polygons, or 'neighbors.' Currently, ArcMap orders the polygons using each polygon's numeric ID. What I ...
1
vote
2answers
65 views
Merging polygons that share one vertex (node neighbors) using ArcGIS Desktop?
I have a set of very large shapefiles and would like to merge polygons within these that share one vertex.
Currently they are all separate like so:
What tool can I use to merge all the polygons ...
3
votes
1answer
50 views
Dissolve (merge) polygons QGIS based on attribute values only when are adjacent
I am a fairly new user of QGIS having a question regarding dissolve functionality.
I am working with the NUTS-2 shapefiles provided by EU, which I have imported in QGIS. I have created a new layer ...
1
vote
1answer
61 views
Using Polygon Neighbors for boundary polygons to find boundary lengths in ArcMap?
I am working in ArcMap. I have a map of districts in South Carolina, and I'm trying to find the boundary length that every district has with every other district, and the boundary of South Carolina ...
0
votes
1answer
29 views
Second-level neighbors of large polygon (neighbors' neighbors)
I have a large-ish set of polygons and am after identifying second-level neighbors of each, that is, the neighbors of the neighbors of each polygon (distinctly, i.e. the 2nd-level neighbors cannot ...
1
vote
1answer
62 views
Extract the “mid/center-point” of the touching borders/lines of adjacent polygons
I have a layer with several polygons and want to extract the "mid/center-point" of the touching borders/lines of adjacent polygons. Despite trying several methods, I do not know how to achieve what I ...
0
votes
1answer
80 views
Identifying/exporting adjacent polygons in ArcGIS Desktop?
I have many polygons (US Counties) with agricultural land data in them. I would like to identify and export (ideally into excel) the data from the counties that are adjacent to the ones with ...
0
votes
1answer
39 views
Selecting coastal census tracts in ArcMap? [closed]
What tool should I use to select or identify geographic units that are adjacent to the U.S. coastline feature in ArcMap?
2
votes
0answers
197 views
Creating Adjacency Matrix using SpatialLinesDataFrame and SpatialPointsDataFrame in R?
I am trying to create an adjacency matrix of power plants that are connected via power lines. The plant data is point data (~8000 observations) with longitude and latitude measurements. The line data ...
1
vote
0answers
91 views
Directions based on polygon centroid and average/median point of adjacent polygon's touching border
I have a layer containing multiple polygons, and I am trying to find a way to identify the directions of the adjacent polygons of a certain polygon. The directions would be based on the main polygon ...
2
votes
0answers
138 views
Postgis List of adjacent LineStrings ordered sequentially from one end of the MultiLineString to the other
I have LineStrings that represent a road network/address centerline that are segmented at intersections, etc. I have determined how to query collections of LineStrings that are adjacent to each other ...
0
votes
0answers
62 views
Calculate Adjacent Fields Issues
I am trying to run the Calculate Adjacent Fields ToolBox on one of my Shapefiles, but the process is taking hours to run, and I have yet to complete the process. My table is 18,000 rows, and so far ...
2
votes
1answer
976 views
Merging adjacent polygons in QGIS
I have a set of polygon layers with thousands of polygons some of which are adjacent (Either rings or simply adjacent). I would like to simplify this polygons by merging them.
Is there a way to do ...
1
vote
1answer
123 views
Adjacency Matrix Not Including Vertices
I have a SpatialPolygonsDataFrame and I would like to create an adjacency matrix. However, I would like to only count two polygons as adjacent if they share more than just vertices (i.e. they share an ...
12
votes
3answers
2k views
Conditional assignment of values to adjacent raster cells?
I have a value raster:
m <- matrix(c(2,4,5,5,2,8,7,3,1,6,
5,7,5,7,1,6,7,2,6,3,
4,7,3,4,5,3,7,9,3,8,
9,3,6,8,3,4,7,3,7,8,
3,3,7,7,5,3,2,8,9,8,
7,6,2,6,5,...
4
votes
1answer
142 views
ArcGIS, detect adjacent polygons with different values
I am developing an ArcMap extension and I need to validate a particular case. I need to detect adjacents polygons that have one value equal, and the others not equal. I you take a look at the image, ...
1
vote
2answers
204 views
Identifying isolated polygons within other polygons ArcGIS for Desktop?
I am using ArcGIS 10.4 for Desktop.
I have a single feature class with one attribute with 5 levels describing the state of grasslands and how they have changed over time. The attached image shows a ...
4
votes
0answers
97 views
Style rule based on feature adjacency?
Is there a way in QGIS to use an expression to define a polygon feature's color based on whether it's adjacent to other features? I would like to achieve something like the following:
-If a feature ...
1
vote
1answer
41 views
Identifying ID of adjacent pipelines?
I work with ArcGIS. In the picture you can see several pipelines, more over pipeID's A; 1; 2; 3
I would like to have as an output the following columns and rows:
A - 1;
A - 2;
A - 3;
As an ...
0
votes
1answer
280 views
Merge adjacent polygons [closed]
I want to write software that merges groups of (mainly) adjacent polygons. For example, merge the US counties into sales regions. Then, display either the boundary of these sales regions or fill them ...
1
vote
0answers
32 views
Merge without dissolve in ArcGIS for Desktop? [duplicate]
I am trying to merge several polygons in a feature dataset into one. Normally I would use a simple merge but the issue is that merge automatically dissolves. I on the other hand want to have them all ...
2
votes
1answer
142 views
Adjacency matrix from TopoJSON
I have a TopoJSON file which describes electoral districts in Montreal, and I would like to produce an adjacency matrix which would tell me which districts share a boundary with which other districts. ...
1
vote
1answer
637 views
Creating lines that connect the centroids of adjacent polygons to one another
I have about 10 polygons, and I have added their centroids to the map. I want to create lines connecting the centroids of each adjacent polygon. If polygon 1 borders polygon 2 and 3, I would like a ...
0
votes
1answer
563 views
Merge touching polygons with keeping their attributes
I've got a layer of polygons
Although they all in the same layer, each polygon own some unique data like the date of this polygon and an amount it possess (a number).
I want to join/merge all the ...
2
votes
1answer
394 views
Adjacency matrix from polygons in GeoJSON
I have a set of polygon features in a GeoJSON file. They are neigbourhoods in Chicago. I would like to produce an adjacency matrix A, in CSV format or any other form, where the i,j element of A is 1 ...
3
votes
0answers
174 views
Adjacency matrix for polygons using Java
I am trying to create an adjacency matrix from a set of polygons. That is, I have a bunch of polygons and I want to identify which polygons have a common edge or "touch" each other. Once I find this ...
1
vote
1answer
52 views
Outputting Polygon Neighbors into special format using ArcPy?
I need Polygon Neighbors to give me data in a specific format. Every polygon should have its own line in the output. Take this, for example(it's obviously not ArcGIS formatted, but it serves the ...
0
votes
1answer
98 views
Selecting/creating polygons of interest based on existing polygon database and indicate other polygons that share boundaries in ArcGIS for Desktop?
I am using ArcGIS 10.2 for Desktop.
The existing polygon database contains attribute table with the following structure, and has three levels; country, state, and city. I am interested in the state ...
1
vote
2answers
241 views
Adding/updating field to polygon feature class that lists bordering (neighbor) polygons?
I have a dataset of zipcodes.
I want to add a new field "NEIGHBORS" that includes bordering polygons in a comma delimited manner such as attached image:
2
votes
1answer
85 views
Trying to extract arc information from a Suburb shapefile
I downloaded some shapefiles from the Australian Bureau of Statistics (ABS). It's basically showing a bunch of suburbs when I view the shapefile through a GIS tool. The GIS tool that I am using at ...
3
votes
1answer
612 views
Extracting polyline of border between differing polygons using R or GRASS?
I have a shapefile with polygons with an associated variable that can take different values. I would like to extract the borders between polygons of differing value (red and blue) as a polyline (dark ...
11
votes
3answers
29k views
Merging adjacent polygons using ArcGIS Desktop?
I want to use ArcGIS Desktop to merge adjacent polygons with each other.
There is no common field between the polygons and hence the Dissolve tool is not the ideal solution. The polygons that I want ...
7
votes
1answer
2k views
Creating Multi-Part Polygons that touch internally using ArcGIS Desktop?
I have a set of parcels as illustrated in the image below. There are currently no multi-part features in dataset. What I would like to do is to merge (not the right word) all of the parcels with same ...
4
votes
5answers
1k views
How to test whether two countries are adjacent using ArcGIS Desktop?
I have an interesting question:
Is there a dataset by which I can use to test whether two countries are adjacent? For example, if inputs are Mexico and U.S., they are adjacent; if inputs are England ...
1
vote
4answers
650 views
Adding information about adjacent features to data using ArcGIS Desktop?
I am working with ArcGIS 10.0. As a simple example let's say I have a map of the United States. I want to each row of the data which states have adjacent boundaries with that state - so that in the ...
23
votes
4answers
5k views
Simplifying adjacent polygons using PostGIS?
I encountered a problem simplifying set of polygons that are adjacent. If I simplify each polygon separately with the Douglas–Peucker algorithm (which is used by many open source tools), the resulting ...
