Questions tagged [connectivity-analysis]
The connectivity-analysis tag has no usage guidance.
34
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Identifying all polygons connected by major river/stream
I'm using ArcGIS Pro. I have a rivers (line) dataset, and a census tract (polygon) dataset. My goal seems relatively simple--polygons are considered "contiguous" if they are connected via a ...
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40
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How to identify dead ends in road network using QGIS? [duplicate]
How to identify dead ends in road network using QGIS? And then how to calculate Street dead ends Density with QGIS?
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102
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Selecting path between two lines using ArcGIS Pro without creating network dataset
I am using ArcGIS Pro 2.9 without a Network Analyst license so I cannot create a network dataset.
In a feature class of connected lines I would like to be able to select any two of them and find a ...
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64
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Road Connectivity Analysis by field
I'm currently trying to do a connectivity analysis of roads of a specific type. (how far can you get before encountering a dirt road?) Ideally, I want the map to look something like this:
It is ...
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182
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Getting geometry network data from File Geodatabase
I have a GDB file with the power distribution utility data set. I was able to get data (File Geodatabase Feature Class) from the GDB file by using QGIS's OpenFileGDB. The remaining information which I ...
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301
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Habitat connectivity analysis difference between Least-Cost and Resistant Kernel Modelling
I have run a MaxEnt model on habitat suitability and transformed this into a resistance surface. I have GPS locations that I am planning on taking a random subsample from to use as termini to run a ...
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502
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Measuring fragmentation metrics of classified map
I have tried downloading FRAGSTATS but this crashes and does not work for some reason.
Is it possible to measure some simple fragmentation metrics on a raster landcover map in ArcGIS Desktop instead?...
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189
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Checking if network has connection errors
I have given a network of a city in dwg.
I made a dxf that only contains the network itself, and created a layer for every type of pipe (like 25KPE, 80KPE etc...).
How do I check if the network is ...
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332
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Merge connected lines [closed]
I have Road Network which was selected based on some criteria. Below is image representing it. Each beginning and end of Road Segment is marked with cross:
Selection led to fragmentation of this ...
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1
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263
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How to count pixels in patches of the Global Surface Water Layer (JRC)
I'm using the GlobalSurfaceWater-Dataset in GEE for creating a mask layer. The mask I do need should only contain water areas bigger than a certain threshold, so I need to get an information on the ...
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Clustering points and summing up attributes per cluster in QGIS
We want to find out the ideal location for sheds and the required dimensions of each shed. As input, we have a point layer with locations (each representing one arable field) and the estimated yield ...
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159
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Calculating connectivity of region?
I have some regions that I have defined and all the public transit in the State, shown here:
The blue blobs are the regions, points are the bus/tram stops, and the lines are the routes.
I want to ...
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49
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How to fix transportation network connectivity problem? [closed]
I am using network analysis in ArcGIS to conduct a health-related analysis of limited resource country. the quality of the road network layer is not high, with many connectivity problems between the ...
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2
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2k
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Selecting connected lines between start and end point in QGIS?
Is there a method in QGIS to select all connected lines that are between a start and end feature (point or selected lines)?
I imagine a workflow going something like this:
Choose the starting line ...
10
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1
answer
2k
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Selecting the longest connected lines from PostGIS ST_ApproximateMedialAxis
I used PostGIS ST_ApproximateMedialAxis to transform polygons representing mountain ranges into a series of lines. Now, I'd like to select only the "longest" line segment for each group, so that I ...
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262
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Filtering out clusters of features based on collective area threshold using QGIS/python?
I have a map I generated that roughly estimates timber industry land ownership (designated by the green on the map) in the counties surrounding the Salish Sea in the US state of Washington:
I want to ...
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287
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Fish passage connectivity analysis using geometric network traces?
We are looking at the connectivity between lakes and the ability of fish to pass between them, considering that downstream presents no barriers for these fish but swimming upstream does (barriers = ...
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814
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The average distance between the roads
I have two vector layers.
Roads Line layer
Roads Point layer
I want somehow to get the average value of the distance between each roads and get average value for my region. Each road has its own ...
3
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1
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392
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Algorithm for Cost Connectivity tool of ArcGIS Spatial Analyst?
For the Cost Connectivity tool in the Spatial Analyst toolbox, what is the algorithm used to compute the minimum spanning tree?
The ArcGIS website includes a general description of how the cost ...
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2
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519
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Using ArcPy to find connected features and update attribute table?
I have a map containing Polylines. There are some blank field names. I want to fill them with the name of connected features. How to use python to find the connected features and update the attribute ...
3
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148
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Examining each connected pixel to select its neighbors to separate clusters using ArcGIS for Desktop? [duplicate]
I am trying to develop a methodology for separating pixels from one another to determine whether they belong to a city cluster or not. Starting at the center pixel of the city I want to select all ...
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178
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What is a good data structure and file format for describing road network geometry AND topology?
I am trying to emulate the road network from OSM or Google (or Waze, etc.) locally, so that I can run some algorithms on it.
For that, I want to represent these roads as graphs, where each edge would ...
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164
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List group of line segments that are not connected to any other lines
In the image below, the system of lines includes 6 segments. This connectivity gives the appearance of an "island" as the internal segments are connected to each other and are not to the outside world....
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83
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Which Network Analyst tool(s) or other geoprocessing tool(s) would be useful for this analysis? [closed]
I have been doing GIS for a few years now but never Network Analyst so I thought I would give this a go. I've built a multimodal network.
Question I want to solve: Using street center lines (walking) ...
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158
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Connectivity of Streams
I have a line vector layer containing streams (see image below). What is the easiest approach to determine the connectivity of each stream segment (eg. sum of upstream nodes)?
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316
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Orphan road segments in QGIS?
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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2
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778
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Calculating forest connectivity for raster
I'm trying to calculate some sort of forest connectivity value for each pixel in my land cover classification. I would like to do this by calculating how many other forest pixels are directly ...
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27
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implement aspect in least cost path analysis to account for downhill and neutral ground movement [duplicate]
I am creating a least cost path model for large species that migrate over large distances across a rugged landscape (elk, deer, etc.)
To calculate movement cost I am using a slope raster but I ...
2
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1
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127
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Find connected features by type in utility network?
I have a storm drain geodatabase with digitized direction flow. I am trying to find catch basins (upstream) that drain to other catchbasins (downstream) as opposed to a junction structure or an ...
4
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3
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897
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Habitat connectivity -- how to map connectivity between polygons based on a separate polygon layer
I have a polygon layer representing a habitat type and another polygon layer representing water features. I want to be able to assign to each water feature whether it shares a connection via a ...
10
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4
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19k
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Checking "connectedness'' of line shapefile in ArcMap?
I inherited a line shapefile in ArcMap that is used to represent a road network. The problem is that the road network is pretty large and it is impossible for me to:
Tell if the end of each line (...
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2
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6k
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Grouping connected linestrings in PostGIS?
I have a table of streets I've selected based on a set of attributes (let's say it's speed_limit < 25). There are groups of streets that are locally contiguous; I'd like to group these sets of ...
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95
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Identifying connected drainage lines
I have a vector layer containing the potential drainage lines that have been computed from a DEM. I want to be able to click on any point and identify all the lines that are connected to my point of ...
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689
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Line segment connectivity analysis in FME
I have a set of line segments, all of them snapped at the endpoints:
As seen in the above image, the line segments appear in groups (4 in this example).
Question:
I would like to determine which ...