Where features overlap

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2answers
205 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 ...
0
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0answers
6 views

Incomplete results from an intersection

I am trying to map the density of buildings in flood-prone areas. In order to do that, I created a grid of equal-sized squares. I want to intersect the layer of buildings with the grid so I can ...
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2answers
37 views

Points within polygon in QGIS [duplicate]

I have a shapefile with polygons. And I have a csv file with points. Now I want to know for each point in which polygon it is situated. Every polygon has a number, so I want to create a file where you ...
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1answer
40 views

Calculate area intersected areas, problem

(I'm working in QuantamGIS) I intersected two layers creating a new layer. Within the attibute table of this new intersect layer i would like to calculate the new areas. However, it just doesn't ...
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2answers
3k views

How to delete overlapping polygon features from one of two layers?

I really need your help! I have two overlapping layers of polygons, and i need to somehow erase the areas the overlaps. -This way i should end up with two layers of non overlapping polygons. Sounds ...
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3answers
37 views

How to find intersections of lines less than 45° in FME

I'm trying to identify intersections of electrical transmission lines that are less than 45° in FME. While, in theory, this doesn't seem like such a daunting task, in practice, it's proving quite ...
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1answer
92 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 ...
5
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1answer
552 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 ...
0
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1answer
352 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 ...
0
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1answer
128 views

Intersecting Overlapping Polygons Individually in ArcGIS

Map Layers: -Census Tract Shape File w/Population Data -Set of Store Locations with 5 Mile Buffers (Significant Overlap Between Buffers) I have create feature layers for both and I am trying to ...
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0answers
15 views

Select features intersecting a linestring in QGIS

I wrote a python plugin that grabs all (vector, linestring) features between two points on the map. At the moment, I select all features intersecting the rectangle around these two points, and then ...
0
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1answer
356 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 ...
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0answers
31 views

Determine if and where 2 paths intersect

I am trying to determine if 2 paths ever intersect and if they do, where they intersect. For example I have 2 coordinate for 2 different paths which I know intersect (I went to ...
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2answers
53 views

Fractional Area Calculation

I have a file (in both raster and vector) of different districts in a country. I have also made a grid of 1 deg * 1 deg (both vector and raster) of the country. I want to calculate the area of each ...
4
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2answers
396 views

Keep nonintersecting polygons during clip

I am using ArcMap 10. I have two datasets, one of which consists of many small contiguous polygons, and one which has many small non-contiguous polygons. The first dataset is census blocks, and the ...
6
votes
1answer
5k views

can I extract overlap of polygons within the same layer?

I am trying to extract the overlap of polygons that are within the same layer in 10. The layer came from a buffered street centerline and I'm trying to extract and delete the intersections from the ...
4
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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 ...
3
votes
1answer
148 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 ...
0
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1answer
29 views

Seperate Intersected layers (as points)

I'm trying to establish watershed outlets as points with two shape files that I have available; i.The watersheds polygons ii. The river network As I said above I'm trying to define the outlets but ...
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0answers
42 views

how to make an intersection between a shapefile and A WMS layer in QGIS 2.8.1

I am using QGIS 2.8.1 I think what I want to do is an intersection between a shapefile and A WMS layer, both in vector format. I have 1 small vector layer that consists of different forest stands, ...
2
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1answer
38 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
37 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
49 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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0answers
9 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
32 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
57 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
19 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
83 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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0answers
24 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
40 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
89 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 ...
1
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1answer
56 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?
17
votes
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
173 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
73 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 ...
1
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1answer
38 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
60 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
88 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 ...
0
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1answer
71 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
votes
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
104 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 = ...
3
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2answers
86 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.
1
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2answers
94 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 ...
0
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2answers
60 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
37 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
48 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 ...
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1answer
49 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
52 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
votes
1answer
106 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 ...
2
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1answer
101 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 ...