Where features overlap

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2answers
189 views

Counting self intersections of linestring using PostGIS?

Is there a way of using PostgreSQL + PostGIS for finding the number of self intersections in a linestring? I have a linestring that goes forward but in circles, and I need to find the number of times ...
2
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1answer
28 views

Extracting intersection areas in R

I have two polygons. One contains fields(X,Y,Z) and the other contains soil types (A,B,C,D). I want to know what area of every field contains which type of soil. I tried the following: ...
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1answer
29 views

Create New Feature Class Based off Multiple Feature Classes

I've searched previous posts to see if anyone asks a similar question, but I haven't found anything. I have a multiple feature classes, each containing multiple polygons. I have two desired outcomes: ...
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1answer
40 views

Intersection of two Raster objects

I have two raster objects r1 (in grey and green) and r2 (in pink) that I want to intersect with R. I tried with the R function intersect from the raster package but it only intersect the extent of the ...
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1answer
546 views

Apportioning Points at a street intersection (arcgis or mapinfo)

I can't seem to find any evidence of this question, but I'm surprised by that, so pardon if this has been asked. If one is mapping crime location reports, by XY coordinates to streets, to create ...
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1answer
343 views

Polygon color on intersect

Using OpenLayers, I am loading a large geojason file of about 4000 polygons. Once the polygons are loaded I want to draw a "LineString" on the map (already done and working). My challenge is that I ...
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0answers
6 views

Finding polygon from two arcs using CLI tools or some library

I'm trying to convert from textual representation into a set of arcs and lines. The 'input' I have is: The area is within lines joining two semicircles with a radius of 0.67 NM centred on: 641139N ...
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1answer
25 views

QGIS - Intersect Spatial GRID and Polygons - Return whole cells on the boundary

I've been managing within QGIS two shapefiles: the first is a spatial square grid, and the second a city region. Now I would like to intersect the grid keeping only the cells that are overlapping the ...
3
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1answer
51 views

How to check if line goes through point with PostGIS

I have a line representing a bus line and a stop representing a bus stop The following sample data represents the problem LINESTRING(-70.65357957000000511 -33.42323483999999922, ...
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1answer
18 views

Trouble updating attributes of a layer based on another layer's attributes if features intersect in python, QGIS

I am trying to assign attributes from features in one layer that intersect features in another layer. When I run my code, I do not get an errors but it does not update the attribute field as I am ...
3
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1answer
70 views

Intersecting lines get crossings

I have a set of lines representing bus lines. Some of the lines are overlapping and take the same roads. I am able to extract the nodes. However I am interested in extracting only crossings like ...
0
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1answer
325 views

Intersecting polygons in Oracle

Have a polygon in table 2 with its id, no and geometry. In table 1 I have polygons with the same fields. The polygon in table in intersects with a few polygons from table 1.What I am trying to do is ...
3
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1answer
138 views

How to calculate the intersected area from a layer with overlapping buffers in qgis

I need to calculate the area of landusetypes in 50m around various dots (all in one shapfile). My problem is, the buffers around the dots are overlapping each over in some places. I tried to ...
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0answers
23 views

How can I redistribute points within a polygon using certain criteria in ArcGIS?

I have some points (representing pharmacies) scattered around my research area and I would like to redistribute those points through the area using the following criteria: The points should ...
1
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1answer
36 views

Function to intersect another polygon using openlayers

I wonder if someone here have a function JS that when I draw a polygon I can see if i drawing on another polygon, like intersect.... if polygon intersect say to me a alert...using openlayers. Thanks! ...
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1answer
78 views

How to intersect FeatureCollections in turf.js efficiently?

I've been playing around with turf.js and I'd like to use turf.intersect to intersect two datasets. My raw data are two polygon shape files so I converted them to geojson. I then tried to use ...
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1answer
44 views

How can I create point to lines intersection qgis?

I have two line layers, and I want to create a point where they cross each other. How can I solve it in Qgis?
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5answers
3k views

PostGIS: Select features that do NOT intersect

This seems to me like such a simple question (and it probably is) yet I cannot seem to find an example that gives me the answer. Using PostGIS, I just want to select points that fall outside of ...
0
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2answers
169 views

Extracting data from four intersecting polygon layers in PostGIS

I've been using the following code in Postgres/PostGIS for the last year, as needed, which is about once a quarter. It works ok, it's just that it takes days to run. With over 25,000 parcels making up ...
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0answers
65 views

How to find co-ordinates of two intersecting features (circle and polyline) in vb.net using arcobjects?

I am new to arcobjects and i want to find the co-ordinates of the intersection points of a circular arc and a polyline. Can somebody please help me with this. I've tried the following code but it is ...
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1answer
37 views

Sdo_Geom.Sdo_Intersection is not considering overlapping vertices

I'm using below package to get the number of intersecting vertices Sdo_Util.Getnumvertices(Sdo_Geom.Sdo_Intersection(B.Geom,R.Geom,.00000000005)) It is returning only 1 when there are actually 15 ...
0
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1answer
43 views

How to crop a basemap to a specific area on ArcGIS

I am a beginner using ArcGIS! I have a base map from ONS of the entire UK... and on another layer I have a boundary outline for the smaller area which I want to crop the base map to. I want to ...
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1answer
78 views

Adding Nodes to Linestrings at Overlapping Points with Polygon Layer in Spatialite

I have two Spatialite tables. A table called 'lines' which contains a PK column called OGC_FID and a LINESTRING column called GEOM. A table called polys which contains a PK column called OGC_FID and ...
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1answer
60 views

Creating many-to-many table from intersection between two polygon layers in QGIS?

I have created a buffer around several points. I want to intersect this layer with a Census Tract layer. My end goal is to create a table that would list all the census tracts that intersect with the ...
4
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1answer
5k views

Create point in intersections of two layers

I have two layers. One of them is 'Road_line' and another one is 'forest_shape'. I want to create a point layer that has points in intersection of that layers. I couldn't find any tools for it.
2
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1answer
82 views

How can I iterate over several layers and run a process using PyQGIS?

I am trying to find road intersections within each of my memory Polyline layers (which are named road_layer_i for i in (0-99)) so this is what I tried: import processing self=qgis.utils layers = ...
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2answers
85 views

Analysis of lines in a point in QGIS

I have 33 layers, 1 with points and 32 with lines. I want to extract/highlight the points where more than one line is intersecting. I have tried with buffers but I'm not getting anywhere.
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2answers
83 views

Intersection point of polygon and the line created by two points ArcPy

I have polygon layer. I selected the most distant vertex from centroid (picture: point A). (How to do that is in the answer here: Select the most distant vertex from polygon's centroid using ...
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2answers
55 views

Intersection between line and polygon

I have 2 layers in openlayers: first is parcel layer (polygons) and second is railway layer (lines). They are already drawn and all i need to do is when i click on some line, to get intersection of ...
0
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1answer
33 views

Using Intersect result

With the help of @Durga I have a working java code for the intersect: gp = new GeoProcessor(); gp.setOverwriteOutput(true); Intersect newintersect = new Intersect(); String in = "(" + ...
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1answer
39 views

Using Intersect tool Java

i am trying to pass polyline and polygon feature classes i am not sure how to pass the list of features to the Intersect object: i tried this method: ArrayList<Object> featuresList = new ...
1
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1answer
39 views

Unable to draw a polygon due to “The feature cannot be added…”

The feature cannot be added because it's geometry collapsed due to intersection avoidance. see also http://i.imgur.com/xiiI7NE.png What happended: Let's say I have 2 layers. To the first I ...
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2answers
51 views

How to intersect two geodatabases in ModelBuilder?

Trying to intersect features from two file geodatabases in model builder. However, the databases can not be connected to the intersect as input features. Second opting - put all features into one ...
3
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1answer
87 views

PostGIS multiple conditional statement on spatial join

I want to make a multiple conditioned spatial query in PostGIS 2.0/PostgreSQL 9.3., OS Windows 7. There are 2 tables, cadastre (Polygon) and roads (Linestring). Query: Select the sum (one number) of ...
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0answers
74 views

QGIS 2.6 simplify a road network to obtain the intersections

In QGIS 2.6.1 in Ubuntu, I want to measure the density of block in this city (FYI my final aim is to measure the TOD level). I have the road network from French national IGN dataset BDTopo. I have ...
2
votes
1answer
92 views

Incomplete intersection area using gIntersection in R

I have two SpatialPolygonsDataFrame, one of them is the deforested area in the Amazon and the other is the city of Vila Rica, which is in the same region. I would like to calculate the total ...
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1answer
48 views

How to compute tabulate intersection in QGIS?

I have a base layer of census data in census tracts (polygons). I'm looking to intersect those tracts with a buffer layer but I only want to include those census tracts whose area is over 50% within ...
1
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2answers
195 views

Integrate grid and polygon of municipalities keeping the biggest municipality per cell with QGIS (or another)

I have a 9x9 grid and a polygon of municipalities of an extensive area of Brazil. My goal is to have a field indicating the biggest municipality per grid cell. I've been trying with intercept without ...
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0answers
25 views

Can a joined-layer have its attribute changed depending on what layers are selected/deselected?

Using QGIS, I have a polygon-grid layer which covers everything, Layer_All joined with 2 other grid layers: Layer_1 and Layer_2, both of which intersect at various points. I would like Layer_All to ...
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0answers
41 views

How to count unique lines intersecting with polygons?

Like u can see on the attached picture i did an intersection with a Raster (purple squares) and the red lines. What i need to know is the count of joins each line has for each square. What makes ...
4
votes
1answer
631 views

How to split a polygon using R

I have an irregular polygon which is a spatial object. I want to divide it into multiple polygons (say, n=25) with equal height. To show how I want to divide it, I've plotted grids on the ...
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0answers
35 views

Determine lat/lon intersection on earth from point in space along 3d line

I have a known point in space with a lat,lon,alt. It has a camera with a line of sight and a angle of field of view. I can take the central point and calculate each corner vector of the field of view, ...
0
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0answers
25 views

Join polygons by plurality overlap

I'm trying to join two layers-- One is census tracts in Michigan; The other is school districts. Because there is no nesting in either direction (districts in multiple tracts and vice versa), I'm ...
0
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1answer
85 views

Oracle Spatial Returns Different Intersection Results with SRID Defined

I have a set of points and a set of polygons of which I am performing an intersection on to determine which polygon each point lies in. This was performed previously without the projection being ...
1
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1answer
55 views

Multi-part Geometrical Intersection error

I am working with intersection of polygon and line segments (continued from a previous question). When a Line intersects with a Polygon, the result is a LineString; When a LineRing intersects with ...
2
votes
1answer
49 views

Isolate features within buffer of another feature - QGIS

I have 2 shapes - one representing line features of pipes, another of roads. I would like to create a separate shapefile consisting only of the pipes that lie within 20m of the roads. Only the ...
1
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3answers
142 views

Query to find the Intersection coordinates of multiple Polyon

I am using the below Query to find out the intersection coordinates of 2 Polygon and its working fine,but how to use or modify the query to find the intersection area coordinates for multiple(or N ...
5
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2answers
526 views

Rgeos drops associated values when intersecting polygons

I am trying to intersect two SpatialPolygonsDataFrames and get a SpatialPolygonsDataFrame as the result. Unfortunately, using the gIntersection function from rgeos (which works impressively quickly ...
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0answers
40 views

How to cut parallelogram with intersecting line?

I have a very specific set of circumstances under which I need to break a parallelogram into 2 pieces. The parallelogram obviously always have 4 vertices and the intersecting line intersects the ...
4
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1answer
154 views

Line vs. Polygon Intersection Coordinates

I am working with Python, Shapely and Fiona... Is there any way where I can give in an input of a line shapefile and a polygon shapefile, and get a result of the intersection points and their ...