Where features overlap

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5
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1answer
480 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 ...
4
votes
0answers
176 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
350 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
47 views

Create circles around a point on a map measuring the radius in hours

Disclaimer: I am not experienced in GIS and hope this question fits in this category. I was wondering whether it is somehow possible to create a circle* around a city, using Google Maps or the like, ...
2
votes
0answers
24 views

Performing buffering and intersection with script in PyQGIS

I wrote a script that performs the intersection of two layers: The first Layer -> layer1, represents the rivers The second Layer -> layer2, represents a set of circular dots distributed in a ...
2
votes
0answers
26 views

Showing Linestring from SQL statement with CartoDB

I have cartodb sql statement to return what polygons are intersected by a linestring, but I'd like to have the linestring visualized over the polygons on the results. Also not add the linestring to ...
2
votes
0answers
22 views

Distribute Hotel Beds According to Population Density in Buffers using ArcGIS for Desktop?

I am running an ArcGIS for Desktop analysis where I am plotting competing hotel facilities and then distributing their beds in a 5-mile buffer around the site. I would like to distribute the beds ...
2
votes
0answers
61 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
213 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
171 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
517 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
35 views

PostGIS - Intersects feature to split into linestring

I would like to know if it's possible to intersect feature datasets (multipolygon, polygon, multilinestring and linestring) to get a result as a set of linestrings being split at each intersection ...
1
vote
0answers
114 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
111 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
75 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 ...
1
vote
0answers
57 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
87 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
49 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
54 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
118 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
49 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
vote
0answers
90 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 ...
1
vote
0answers
89 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
vote
0answers
264 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
223 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
244 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
104 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
23 views

Iterating Intersect Between Dates for single and dual shapefiles of multiple polygons

I'm looking at day range overlap for an animal - to do this I'm looking to generate intersection polygons from the animal's range on day 1 to day 2, then day 2 to day 3 etc., from day 1 to the end of ...
0
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0answers
17 views

Basic Intersect in mysql

I've looked all over but can't find a simple snippet of mysql spatial intersect. Does mysql support it? Does anyone have a working exmaple? Thanks
0
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0answers
34 views

How to overlay polygons that are in the same layer

I need to INTERSECT many polygons that are in the same layer. Actually each polygons from my layer represent an area of influence from one specific bird species. Since I used to use ArcMap, I found ...
0
votes
0answers
34 views

Determine the list of circles (from 100K circles), that overlap with a given polygon

This question was asked on StackOverflow, came here because no response has been posted so far. Existing data structure we have polygons represented as an ordered list of lat/long coordinates and ...
0
votes
0answers
57 views

Using Geometry commands in MS SQL Server 2008

I am looking to find the most effect way to use SDE and ST_Geometry SQL commands. Can anyone tell me how/what commands I might use to perform a spatial query in MS Sql Server 2008, to Select property ...
0
votes
0answers
24 views

How to measure water ties

I was using Arc Gis to measure water ties from the edge of buildings. It was so easy, I just had to click on a circle and it would show the distance on the bottom of the screen. I would measure from ...
0
votes
0answers
36 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
42 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
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0answers
16 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
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0answers
44 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
34 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
42 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
23 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
61 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
votes
0answers
87 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
votes
0answers
21 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
votes
0answers
94 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
175 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
169 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
votes
0answers
18 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
votes
0answers
71 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
777 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 ...