Where features overlap

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5
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1answer
425 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 ...
3
votes
1answer
65 views

Find intercept WGS84 coordinates between two segments defined by (Lat1-Long1 and Lat2-Long2) and (Lat3-Long3 and Lat4-Long4)

I need to determine the WGS84 coordinates for a point that is defined by the interception of two segments represented by two sets of WGS84 coordinates each (lat1-long1, lat2-long2) and (lat3-long3, ...
2
votes
1answer
143 views

Creating buffers that will not overlap in QGIS

I am dealing with a .shp with a number of points in it. The distances between points range from ~300m to 5km. I wish to create a 1 km buffer around each point with as little overlap as possible. Each ...
2
votes
1answer
93 views

Separate a polygon in different polygons depending of the distance to another polygon

I have a reference polygon "R", and others polygons (in grey). I want to separate each grey polygon in multiple polygons, depending on the distance to R with different Buffers : - The red line is R ...
4
votes
0answers
141 views

Cut polygon and retain data

I have these two polygons: library(sp); library(rgeos); library(maptools) coords1 <- matrix(c(-1.841960, -1.823464, -1.838623, -1.841960, 55.663696, 55.659178, 55.650841, ...
4
votes
0answers
288 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 ...
2
votes
0answers
48 views

How to copy the contents of an attribute from one vector layer to another one that touches it or intersects it?

I have 2 layers that intersect, called layer A and layer B. Layer A has an attribute (X) that I want to copy wholesale (for the whole layer) to layer B, so that when object A1 intersects object B1, ...
2
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0answers
164 views

3D features (Polyline, Polygon) intersection library

For my research I am looking for a (python) library to get the intersection of some 3D features. The features can be Polygons or Polylines. Mostly I need to intersect a plane with my features and get ...
2
votes
0answers
159 views

How could I make this PostGIS query run faster?

SELECT st_band(rast, 1), st_width(rast), st_height(rast), st_bandpixeltype(rast, 1), st_bandnodatavalue(rast, 1), st_scalex(rast), st_scaley(rast), st_upperleftx(rast), st_upperlefty(rast) FROM ...
2
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0answers
459 views

cant find point/polygon intersect using qgis (windows only)

below i describe the method i am using. i have 2 machines: 1 ubuntu linux, qgis 1.4 - intersection works 2 WIN xp, qgis 1.8 - intersection dows not work hopefully, someone will ...
1
vote
0answers
16 views

How to set tolerance value of ST_Intersects query in TileMill?

I want to place river names in Tilemill. I use "text-dy" to displace label from the center line of a river. But for labeling polygonal rivers, names extracted from lines are used too. So at a small ...
1
vote
0answers
45 views

How to count points once with overlappying polygons?

All, We're using parcel data (polygon) to count student locations (point) based on parcel type. We're doing this using SQL and the ST_Intersects function. It works great, except the City and County ...
1
vote
0answers
39 views

How to simplify a self intersected / self overlapped polyline using ArcObjects?

I have a self intersected polyline, how can I break it into 5 records stored in the same table using arcobjects? (splited by vertices and the intersection point) Here is what I have got and it ...
1
vote
0answers
45 views

PostGIS: How to distinguish overlapping routes (i.e., LineStrings) based on their direction?

I have a set of routes which are represented by LineStrings in my PostGIS database. These routes represent journeys that people make. I want to come up with routes that (a) overlap, and (b) have the ...
1
vote
0answers
43 views

How to Simulate Venn Diagram of Buffers using QGIS?

For the sake of simplicity, suppose I have only 2 points on one layer. Point A have population of 100, and point B have population of 150. I do find buffer of these 2 points and it is intersect. I ...
1
vote
0answers
49 views

Intersection between a ray from lat, lon, alt, with pan, tilt and earth's surface

I have a problem that consists of finding the intersection point between a ray from a given lat, lon, alt, that is looking to a given pan and tilt angles and the earth's surface. I need the lat, lon ...
1
vote
0answers
28 views

How to get intersected points between polygon and line in desired order

I have polygon for example "POLYGON((5 1, 6 1, 6 5, 5 5, 5 1))" that I want to intersect with line "LINESTRING(0 2, 10 2, 10 3, 0 3, 0 4, 10 4)" and get intersection points in the order that they ...
1
vote
0answers
39 views

Trouble intersecting a polyline and contours (Hack index / stream length gradient index)

Working on creating polylines for measurement using SL index (hack index). So far I have the main trunk of a stream, and contours at 10m. What I am trying to do is a) get the elevation at each ...
1
vote
0answers
73 views

How to best intersect vector data with raster data?

I have Open Street Map [OSM] data imported so that I can access the geometry of buildings. I have also loaded SRTM digital height data from NASA from a GeoTIFF raster. I have projected the raster into ...
1
vote
0answers
45 views

Broadband coverage GIF image layer needs to be selectable (ArcGIS)

I am working on a project on Arcmap where I have 80,000 co-ordinates of postcodes and a broadband coverage map. I need to know which of the co-ordinates intersect with the coverage map. I have added ...
1
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0answers
83 views

Gdal/Ogr - OGRLayer.Intersection() Question

I was trying to perform intersection on two feature classes (shape file format) using OGRLayer.Intersection(), but have problems making it work with C# bindings. I am not able to figure out on how to ...
1
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0answers
217 views

intersect two shape files using QGIS API

I am trying to automate a process of a shape file. We are using google maps engine and we have limitation on number vertices in a shape file. so I am using a grid to split the shape files. In GUI , I ...
1
vote
0answers
31 views

Suggestions for vector format for polygons

I am using two polygon tables in postgis (A and B ). I need to make a vector file that incorporates information of the overlapped polygons B intersecting each polygon on (A). I can make a single ...
1
vote
0answers
179 views

How to handle/ avoid intersect errors when clipping the difference between two layers?

Using QGIS + Grass, I've added a shapefile of coastline and islands to my map. I then buffer this shapefile to create a coastal zone of a known width. At this stage the buffer consists of the ...
1
vote
0answers
226 views

error in gp.execute intersect

i generate a tool to return values using area of polygons. but when i execute the tool, visual studio show an error :"Error HRESULT E_FAIL has been returned from a call to a COM component" in ...
1
vote
0answers
103 views

Copied points not intersecting the original points

I'm using an arcpy search cursor to access a Oracle database. I have a simple Python class that I copy the returned row objects into, which gives me more flexiblity than the cursor. The problem is ...
0
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0answers
19 views

Split polygon into four with respect to single point

Some days ago one of my colleague came to ask me a query related to Geometries. The situation is as....There is one Polygon(suppose a city polygon) and there is one point(suppose user's current ...
0
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0answers
22 views

How to intersect more than 2 layers in QGIS

I have a dozen layers, some intersecting with others. Using the Intersect tool only allows 2 layers at a time but can you add extra layers to find where it intersects? Even if it's 3 layers as shown ...
0
votes
0answers
11 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 ...
0
votes
0answers
24 views

How to use Intersect tool in ArcObjects

I'm trying to use the Intersect tool in ArcObjects SDK Java with two feature classes. Here is my code: public void intersectTwoFeatureClasses(Object in1, Object in2, Object out) throws ...
0
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0answers
15 views

GRASS GIS - v.select- ERROR: bad allocation -

I'm quite new to Grass GIS. I have two vector maps, one of a grid (each grid cell is a polygon) and one of a much larger polygon. I've been trying to select the grid cells that lie completely within ...
0
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0answers
25 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 ...
0
votes
0answers
21 views

Using M 'Measure' value in SQL Server 2008

MS Sql Server 2008 geometry type supports adding Z and M values to geometry objects, including linestrings. However, I cannot find any way to make use of these values, since methods such as ...
0
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0answers
21 views

Method of extracting the intersecting areas of multiple overlapping polygons (5) and classifying intersects based on spatially joined points

I have concave hulls surrounding clusters of data points which has led me to a lot of overlap and fuzzy boundaries. I am attempting to intersect the overlapping areas but have a minimum of 5 different ...
0
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0answers
41 views

Arcobjects/Arcgis Engine — geoprocessing within a buffer?

I have a point layer and a polyline layer (each contains more than 100k records), I would like to process the polyline layer within point buffer zones. For example, for each point in the point layer, ...
0
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0answers
55 views

Draw point on google map

i try to add google map on my own wms and wfs layer. everything works but when i create point, i intersect point geometry and my geojson data. So without googlemap it was run. But when add google map, ...
0
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0answers
19 views

Program crashes when trying to do intersection.

I'm trying to get the intersection between a highways shapefile and some states in Mexico but it seems that the program always crashes. I attach the images of what I'm trying to do and the error that ...
0
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0answers
66 views

Line - Line and Line - Polygon intersection in WGS84

What is the correct way (which formula, what algorithm, etc) to determine the intersection point of two lines specified in Lat/Lon coordinates on a WGS84 model? Note that the lines might be very long ...
0
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0answers
133 views

Computing percentage of similarity between two line strings using python shapely

I'm quite new to shapely, been tinkering with it and I have a necessity to compare two line strings and see what percentage of them overlap. The geographic coordinates come from two different systems. ...
0
votes
0answers
132 views

Creating a BATCH with multiple INPUTS (variables) to run a workbench that intersects LINES AND POLYGONS

I'm trying to create a batch file to run my workbench.fmw in which I have two input files: 8 pipeline shapefiles and 96 communal areas shapefiles. The workbench allows cutting pipeline relative to the ...
0
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0answers
17 views

Whis is my QGIS vector intersect sticking at 10%?

I'm using QGIS and attemptin to create an intersect layer for 2 vector layers. However every time I start the operation it works for approximately 2 minutes, and gets t around 10% and then sticks. Is ...
0
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0answers
61 views

Vector/Raster Intersection - Speedup and replacement for ST_Centroid

I have some raster data which is the altitude above sea level and also some vector data which represents building outlines. What I want to do is grab some buildings outlines and fetch all the raster ...
0
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0answers
78 views

how to avoid Intersection of polygons via python code

i am using QGIS 1.8 and i can set the check box in Setting\Snapping Options "Snapping and Digitizing " dialog to avoid polygon intersections and enable topological editing but i am looking for a way ...
0
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0answers
26 views

ERROR: CASE types geomval and geometry cannot be matched

I am trying to optimise the speed of the intersection query that I am running. However, I am struggling to find the best way to do this. And found a similar bit of sql that looks like it would do ...
0
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0answers
173 views

QGIS - Intersect two shape files

I need to create a new shapefile from two existing shapefiles with QGIS. The original shapefiles are both for the US and contain the borders of congress districts in different years (the borders ...
0
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0answers
497 views

Vector Intersect QGIS (1.8.0) Gives empty shapefile

I am trying to find points that fall within a polygon. Both layers are vector ESRI shapefiles. I used the fTools based intersect under Vector>GeoprocessingTools>Intersect. The output is an empty ...
0
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0answers
90 views

polygon/raster intersection artifacts

I'm intesecting a polygon with a raster using PostGIS > 2.0. The outer boundary of the polygon is formed by the convex hull of polygons (building outlines plus safety margin) and the inner rings are ...
0
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0answers
31 views

GEOS: How to intersect without noding?

As discussed in this question intersecting two GEOS line geometries gives a result which has also been noded. This is very nice if noding is what you want, but is it possible (through the C api) to ...
-1
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0answers
36 views

How to set input parameters for geoprocessing task that uses Intersect tool?

I have tried to create a geoprocessing task that allows the intersection of two or more layers from my map service. For that I created a model, using ModelBuilder, and I published it as a ...
-2
votes
0answers
39 views

intersect zip python

I try to change the python script ExtractData to do the intersection., but until now I fails to do so. i change the funtion : clip_analysis by intersect_analysis. i change also the parameters: ...