Where features overlap

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11 views

PyQGIS: intersection of one node layer with two polygon layers

I´m new with the use of PyQGIS and I´m working in a problem applied to a water supply systems modelling, where I need to distribute the water demand in about 5000 nodes (network junctions). I´m ...
4
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3answers
145 views

Finding redundancy between two layers

Let's say I have two point layers that contain locations of wells on a property. layer A has 50 points. layer B has 35 points. Some of layer B's points already exist on layer A, and some of them ...
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1answer
35 views

PostGIS ST_Difference function returns wrong geometry in result

I have a strange st_difference behaviour. I’ve got two overlapping lines (each one has two points), but st_difference result is complete geometry of the first line. The code to reproduce is here: ...
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1answer
31 views

Updating table setting a case with ST_Intersection

I'm trying to update a geometry column using this command: UPDATE mad SET geom_p=CASE WHEN ST_CoveredBy(mad.geom,b.geom) THEN mad.geom ELSE ST_Multi(ST_Intersection(mad.geom,b.geom)) END AS ...
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2answers
47 views

Calculate area parts of polygon intersections

I have a problem of calculating area sizes of intersected polygons in postgis. I would represent the problem in an example (please see the picture). I have a gridsquare table with some attributes like ...
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1answer
33 views

Create a point at intersection

I want to create a point at the intersection of two lines as it appears on the attached image. The red line is the stream network, and the green line is the 600m contour. I use ArcGis 10.2.2
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2answers
71 views

GDAL/OGR ogr.Layer.Intersection fails when producing mixed geometry results

I am trying to intersect layers using the ogr.Layer.Intersection method, in Python. This works fine for pairs of polygons, but I have found intersecting two linestring layers containing matching ...
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2answers
45 views

Arcpy fail to loop between files in different directories

I want to perform a loop of intersections between different files in different directories. Here is my code: Intersects = ['Name1','Name2','Name3','Name4','Name5'] #Names of my files ...
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0answers
27 views

How to use the “geometry generator” to intersect geometries with an entire layer in QGIS?

In the "geometry generator" style in QGIS, it's possible to define an intersection for a specific geometry of an other layer like this: intersection($geometry, geometry(get_feature( ...
2
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1answer
43 views

QGIS: intersect on a single shape file

I am using QGIS version 2.14.1 (Essen). I'm trying to do some spatial analysis, including an intersect between the same shape file. Basically I have a shape file with the geometries of all the events ...
2
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1answer
42 views

Get intersection of circles shapely

I have a List of Points which I transform to circles. Code from here circles = [Point(random.random(), random.random()).buffer(random.random() * 0.1) for i in range(3)] I want to know which circles ...
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4answers
78 views

Count Points on Points using arcpy

I have a point feature class which contains features scattered around the city, with some of the points intersecting other points. These intersecting features are correctly different features (they ...
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1answer
31 views

How to check point intersection with bbox made from two points?

I have two points which represents lower left and upper right point of BBOX. I have one point which SHOULD be somewhere inside and I want to test it. I have all of them as 'geometry(POINT, 4326)' ...
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0answers
22 views

Can turf.js be used to find and repair bad geojson geometry?

Methods: I'm currently using turf.js for geoprocessing as part of a broader mapping project; my workflow looks like this: Pull geojson of census tracts for an entire county Pull geojson tiles of ...
0
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1answer
25 views

Tabulate intersect in R

I would like to get the areas related to the polygons resulting from the intersection between two SpatialPolygonsDataFrames: 'A' and 'B'. SpatialPolygonsDataFrame 'B' has 3 different 'classes', which ...
3
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3answers
71 views

How to calculate the difference in area between two overlapping polygons?

I have two polygons that are overlapping each other. I need to calculate the area that's created in between these overlapping polygons. I used the "intersect" tool but it's not giving me the exact ...
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1answer
37 views

How to find the area with most intersection for buffer regions?

Find the area with the most intersection This question relates to previous question asked - How to find the intersection areas of overlapping buffer zones in single shapefile?. I tried to ...
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1answer
25 views

Intersection with 2 KML files - newbie

I'm new to all this gis thing and I have this project for university where I'm trying to find the countries within a bounding box. So what I'm doing is, I have a set of coordinates that define a ...
2
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1answer
95 views

How to find the intersection areas of overlapping buffer zones in single shapefile?

Find the intersections of the buffer zones I found an example where they tried finding the intersection of two different shapefiles -Intersect Shapefiles using Shapely. I've tried to adapt my code to ...
5
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1answer
103 views

How to get smallest line segments from intersection + difference of multiple overlapping lines?

Inspired by this question, and this excellent answer. I have multiple overlapping lines and want to extract the complete intersection of them. So from this sample data SELECT id, geom INTO stackex ...
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0answers
14 views

Select simple intersection

Using PostGIS, I want to select avenues that intersect trajectories (linestrings, which I want to add a ST_Buffer). I'm thinking that maybe some syntax is incorrect... I tried this, but do not work: ...
2
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0answers
43 views

QGIS Atlas zoom to intersection between two different layers

I have two polygon layers, one is about different land owners boundaries and is used for atlas generation, and the other is about forests inside each property. In atlas generation sometimes i want to ...
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0answers
41 views

Select Layer By Location (Management) gives different result in ArcPy and ArcMap?

I have two line Shape files. When I use the Select layer by location tool to select two intersecting lines, it works fine and selects only lines which are actually intersecting. But when I use this ...
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0answers
39 views

Intersect two same extent shapefiles, but got error 000117

I have used intersect(Analysis Tool) to intersect two polygon layers. But I got error 000117 after ran intersect tool. Same error message happened when I use clip (Analysis Tool). The answer and two ...
2
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0answers
43 views

Identifying lines of one feature class that touch another feature class with their endpoints in ArcMap? [closed]

I want to find out and select the features of one feature class, which both endpoints touch another feature class. In the picture above it would be the left pink line which touches feature of ...
0
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1answer
38 views

Unexpected results when using ST_Intersection for polygon features

I've to create a spatial intersection of two tables (poly_a and poly_b) containing polygon features. Is there any way to remove unexpected linestring results? CREATE VIEW poly_intersection AS SELECT ...
2
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1answer
27 views

Split No Longer Working When Creating Enclosed Polygons

I have been using ArcGIS Pro to create a large polygon feature class. Some of the polygons have enclosed areas I need to remove. I have been using the Split tool under Modify Features and it has ...
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0answers
20 views

How do I find whether a line is intersecting a circles with small radius on earth?

Algorithm mentioned in how-to-pick-up-line-segments-which-is-inside-or-intersect-a-circle seems to be working fine for circle with radius > 50 miles. But when coming to circles with radius < 50 ...
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1answer
20 views

Counting points on a line or polygon using join: number of points are calculated incorrectly [closed]

I am attempting to count the number of stream crossings within approx. 100m segments of a trail. I used this article to get quite close with join: ...
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1answer
57 views

Read SQL Server Geometry datatype in R

I have two datasets that come from ArcGis, stored in SQL Server. I have a column called - Shape which is a geometry data type and the value looks like this: ...
2
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1answer
36 views

edit vertices of intersections from multiple lines

I would like to edit the vertex where two lines intersect, but doing so makes me manually move each vertex of each line. I tried to merge the lines but it did not work. Is there an easier way to ...
2
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2answers
83 views

SQL Server - Select all polygons nested within a larger polygon

This is a seemingly simple SQL Server geometry question that I thought would have an out-of-the box solution, but I'm not having any luck finding one. My intent is to select all the records within ...
1
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2answers
74 views

How to find the intersection of three polygon layers in ArcGIS?

I have three data sets of San Francisco, TerraSAR-X, ALOS-PALSAR, Radarsat2. I have extracted KML files using Envi Sarscape. In order to find the intersection of these areas, I have converted ...
2
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1answer
29 views

Preprocess OSM streets to see if query points fall “on” them

I am interested in the following query: Given a set of query points ($\leq 10$), how many of them have distance at most $s$ meters to the closest point on the closest street. What's the most ...
3
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1answer
114 views

Strange behavior of of ST_Intersects in PostGIS

I'm quite new to GIS and PostGIS and, probably, this question has been already answered multiple times, but unfortunately I was not able to find an answer. I have few polygons and I want to find ...
1
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0answers
25 views

PostGIS Street Intersection Autocomplete with full text search

What I'm attempting to do is create a custom autocomplete for addresses, road intersections, POI's, etc. For now we are going to using Mapbox GL (we'll be creating a custom map at a later phase), ...
1
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1answer
52 views

ST_Intersection between MultiPolygon tables leads to gaps, missing intersections

I am trying to intersect two MultiPolygon tables, which are in the same UTM projection, and calculate the area of their intersections. I am getting some surprising results when I examine the ...
3
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0answers
47 views

QgsSpatialIndex partial or complete overlap

I'm working on adding some functonality to a QGIS plugin. It currently uses a QgsSpatialIndex to efficiently compute whether the features of a vector layer intersect (potentially millions) of ...
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0answers
38 views

How to collect values from iterated intersections, in ModelBuilder

I have a points feature class which I am intersecting with a number of polygon feature classes, one at a time (i.e. points AND polygons1, points AND polygons2, etc...). Each time I do an ...
5
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1answer
92 views

Find all intersections of a LineString and a Polygon and the order in which it intersects it

I would like to find out all intersections of a LineString (River) through Polygons (Municipalities). I would like to list the order of municipalities which the river crosses, using linear ...
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0answers
14 views

Intersect Iso_rectangle_2 with Polygon_2 where Polygon_2 uses Projection_traits_xy_3

I have a set of [Point_3][2] that constitute a Polygon_2 using the Projection_traits_xy_3 typedef CGAL::Exact_predicates_inexact_constructions_kernel K; typedef CGAL::Projection_traits_xy_3<K> ...
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0answers
83 views

Calculating area of intersection of polygon to another layer in ArcGIS for Desktop?

I am very new to GIS, especially ArcGIS. I am currently using ArcGIS 10.2, and I have 2 layer, namely the purple feature map(this layer is an import from arcgis online, it doesn't seems to be an ...
3
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1answer
70 views

ArcGIS find all polygons that intersect with more that one polygon from another layer

I have two layers with polygons. I want to find those polygons from first layer that intersect with more that 1 polygon from second layer and find those intersected polygons ID numbers: 1 from first ...
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0answers
21 views

Subset of spatial data causes slow SQL Spatial STIntersects

I've been having an issue were a specific subset of data causes an SQL spatial intersect to run extremely slowly. I am running sets of 1000 points against a subset of polygon layer to be intersected. ...
4
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0answers
47 views

Why won't my points (that I created by intersection) won't intersect with the geometry they've been created from?

I created a set of points by intersecting a linestring layer with the boundary of a multipolygon layer like this: CREATE TABLE freiraumkataster_grenze AS SELECT gid, ...
2
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0answers
75 views

Intersect, Spatial Join?: One Line crossing Multiple Polygons, assigned wrong attribute

I am looking for any possible solutions to a problem I am encountering with ArcGIS. I am using census block groups (CBG) to assign streets an income level value based on their location within the ...
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1answer
166 views

Problem intersecting shapefiles with OGR in Python

I'm trying to move from ArcPy for geoprocessing. After searching some posts, I found this solution using the GDAL/OGR Python bindings: Intersect Shapefiles using Shapely My code is the following: ...
3
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1answer
74 views

Rotate symbols perpendicular to line angle (QGIS)

I have lines representing curving streams and want to angle symbols at various points on the streams so that they are perpendicular to the angle in their particular locations. What QGIS seems to do ...
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0answers
20 views

How to Find Source and target using STBuffer And STIntersects in SQL Server?

I am using this query to find the source and target from Routes table, but it's not getting the correct result SELECT TOP 1 a.target FROM Routes a WHERE ...
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1answer
34 views

Tabular Intersection producing Empty Output Why?

I am trying to run a Tabular Intersection on ArcGIS 10.2.2 between a 1000m buffer and a forest layer to establish the percentage cover and total area of trees within the buffer areas. Everytime I run ...