A region enclosing a point, line, or polygon at a specified distance.

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0
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1answer
311 views

Can osm2po produce a travel distance buffer for a given time?

Given a starting point and a travel time, I would like to produce a travel distance polygon. Can I request this from osm2po via http?
3
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1answer
262 views

How to represent Typhoon(s) wind speed using Quantum GIS / PostGIS?

I am not completly new to GIS (was taught ArcGIS at Uni) but I would still consider myself (especially compared to all these experts here) a newbie in QGIS or PostGIS. I want to display the ...
4
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1answer
2k views

How to create fixed length (and width) buffer around a polyline in ArcMap 10?

Could someone please help me? I would need to create 100 buffers (500m x 1km) along a stream polylines. I know how to do it by using shortest distance but the buffers should follow the curves of the ...
1
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0answers
205 views

Geoserver not buffering external graphic in PointSymbolizer

We've got some Point data we're displaying in a WMS layer using geoserver 2.2 (same problem on 2.3.1). We style it with the following SLD <Rule> <PointSymbolizer> <Graphic> ...
1
vote
1answer
463 views

Extraction of raster cell values based on 'rgeos' and 'raster' buffering approaches in R

I am trying to extract cell values from a raster that lie within a certain distance from a given location (i.e. buffering). Evaluating different approaches, I found out that applying gBuffer(..., ...
2
votes
2answers
263 views

How to calculate land cover inside the buffer zones?

In one Shape file I have created 1200 buffer zones Around coordinates. I created a field and calculated the buffer zones area in hectares. Then I clipped different landcover layers to the buffer ...
1
vote
1answer
253 views

How do I convert MultiLines to MultiPolygons using Postgis

In postgis I'm using the following query to buffer lines to polygons: UPDATE rivers SET poly = ST_Multi(ST_Buffer(lines, 0.01)) where id = 1; The column 'lines' is a MultiLine and the column ...
1
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2answers
77 views

Plotting a circle on a Web map to view the resulting coverage over a central location

Not exactly a GIS question but I hope no one will mind. Does anyone know of a website (something equivalent to Google Map) where you can indicate a location, give a radius and you can view the ...
4
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3answers
3k views

Conflicting measurement units with buffer ftools

I am new to qgis and I would like to create a buffer around point features. My goal is to create a quarter mile buffer (402.336m) around each point feature, using Geoprocessing Tools -> Buffer(s), ...
1
vote
1answer
188 views

Need to make a buffer around a part of a feature, keeping other features attached

Basic problem: I have two layers, a layer containing river basin outlines and a layer of wetland outlines and types. I need to make a buffer around one river basin, and then create 100 random points ...
2
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0answers
320 views

Proximity Toolset Questions - Description, Examples of Usage, and Limitations

I was wondering if you could help me answer a few questions about the Proximity Toolset. I have been given the task of describing each tool in laymen terms, the typical usage of each tool, and most ...
1
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0answers
87 views

Clipping Buffers

I have buffered a line shapefile where many lines are intersecting but not broken at intersections. I am trying to select each record in the buffer file and clip all intersecting polygons in the same ...
1
vote
1answer
106 views

problem of buffering a point on large areas with a projected coordinate system

could someone clear this up for me please. i remember reading an article not long ago on the web about the problems associated with buffering points on a globe due to the fact that a globe uses angles ...
0
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0answers
189 views

Offset a Polygon defined in Lat Lng points by a given distance of miles or km

I am trying apply a positive offset/buffer (enlarge a shape equally from the borders) to a polygon that is made up of a series of latitude/longitude coordinates by a distance that is defined in either ...
2
votes
1answer
80 views

Clipping a buffer from network analyst shapefile to a base shapefile

I have exported my polygon shapefile which I got after I ran my Network Analyst into a shapefile. It has 6 buffer zones (delimited by time in increments of 10 minutes). When I check the attribute ...
6
votes
1answer
596 views

QGIS define hexagon area around mapped points

I am using QGIS to map a number of radio antennas (for mobile network). Once I have the layer of the sites (done), I would like to assign to each site a coverage area (envelope). I could achieve that ...
2
votes
1answer
119 views

How to create a buffer zone for notification

I am new to PostGIS. I am working on a project, for this i need to find out abutter notification that generates a list of properties within the buffer zone from the selected property with user input ...
4
votes
1answer
287 views

Distance from waterways

I have an sdc file with water bodies, i.e. oceans-rivers-lakes. I want to combine it with a shapefile with the boundaries of countries all over the world and produce two measures: 1) The average ...
1
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0answers
219 views

Clipping points using buffer in Arcmap takes FOREVER

I'm clipping points (crimes) by using a buffer around a shapefile of city parks. There are quite a few records involved (2 million+), but it is still taking forever - as of now, the clip has been ...
8
votes
2answers
2k views

How to buffer a vector shapefile using ogr python?

I am trying to learn how to use ogr in python using the country and populated places datasets from http://www.naturalearthdata.com/downloads/50m-cultural-vectors/. I am attempting to use filters and ...
2
votes
0answers
385 views

Multiple ring buffer on point-shape error

I need to calculate multiple ring-buffers, but every time I try, arcgis produces a failure: Executing (Multiple Ring Buffer): MultipleRingBuffer Y:\GIS\RDY\clip\sn_clip.shp ...
4
votes
2answers
413 views

PostGIS algorithm to unite points of two geometries that are within specified radius

I want to find an PostGIS algorithm to unite points of two geometries that are "near" to each other. That is: I want a function, that takes as input two geometries, and returns 1 geometry, that ...
3
votes
1answer
800 views

How to Get the Three Nearest Points to an Object (different layer)?

I have two point shapefiles and I want for each point in the 1st shapefile to get the 3 closest (based on air distance) points from the 2nd shapefile. If possible, it would be great to have each of ...
6
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2answers
2k views

What's the Workflow for buffering in meters/km using WGS84 layers?

I'm a little bit new to GIS, so bear with me a minute.... I'm using QGIS 1.7.4-Wroclaw and working with an SHP layer in WGS84. I want to buffer out to a certain number of kilometers from this layer ...
1
vote
1answer
822 views

Create buffer-lines in QGIS alongside Vector lines

I am currently doing a map of a farm, to see which roads needs to be repaired. Those roads are either one sided fenced, on both sides fenced or not fenced at all. I want to make buffer lines around ...
0
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0answers
120 views

trying to make a point to polygon attribute join with a many to many match

I am trying to match US charter schools to noncharter schools in QGIS. I have constructed a buffer of 10 miles around each charter schools and then tried a join attributes by location match with non ...
0
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2answers
622 views

How to remove overlapping buffer in QGIS?

I wanna know how to do this in QGIS: I've tried many ways, but still can't find the right solution.
0
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1answer
125 views

Creating rectangle over a buffer circle with specified angles/rotation?

I have a layer that is a circle buffer around a point. What I want to do is create a rectangle around the circle, but have every rectangle be perfectly lined up N/S (0degrees of angle/rotation). I ...
12
votes
4answers
2k views

How to buffer in pyQGIS?

I'm looking for some examples to do simple python scripts in QGIS. How would I do a buffer analysis on a dataset? I can't seem to find much in the manual and QGIS python that quite matches the Esri ...
3
votes
2answers
4k views

find location details within circle buffer

Wondering how would i go about getting this to work. I have a table with location data (lat, long, homevalue) in sql server 2008. Given a lat long say (32.113, -81.3225), i want to draw a 50 mile ...
1
vote
1answer
257 views

How to fit a polygon to a “best buffer” about a reference geometry in it?

If I have a polygonal geometry gbase, like a street (a rectangular strip), and a reference geometry gref, like a central line of gbase. The question is what is the function (here named BestBuffer) ...
3
votes
1answer
666 views

FME remove polygon holes of under size ### sqft and chop the ends off

Quetion #1 I have a wokspace that takes the latest version of my data and creates buffers and then merges those to one polygon. When 2 buffer polygons are near each other and close to create a hole. I ...
5
votes
1answer
502 views

How can I create a pollutant dispersion raster in QGIS?

As my previous questions have indicated, I am working on an air quality problem where I have a dataset of industrial emissions that consists of a location (long, lat), and an annual volume of ...
5
votes
1answer
159 views

How do I find location of minimum value within a buffer (around a point)

I have a digital elevation model (DEM) with a point location defined. I want to locate the lowest height values at a set distance from this point. I envisaged creating a buffer around the point ...
5
votes
3answers
832 views

Is it possible, in QGIS, to create buffers with a set radius, but with individual values taken from the attribute table?

I am looking to create an output that consists of an 11KM buffer around a number of discrete points, where the buffer has a value defined by a column in the data sets attribute table. Is this ...
2
votes
3answers
2k views

ERROR 000800 when trying to snap points layer to line or buffer layer

I am very new to GIS, so go easy on me. I am using ArcCatalog 10.0 and trying to snap a set of points to another layer that has roads in it. The points represent 10th miles along the road. Here are ...
1
vote
1answer
923 views

create buffer around locator-derived point

I am trying to create a buffer around a point derived from a locator search, using this example: http://help.arcgis.com/en/webapi/javascript/arcgis/help/jssamples_start.htm ..but I am getting no ...
0
votes
6answers
4k views

batch buffer with python in arcgis 10

Hi friends: i have some feature class(7 feature classes) and I want to batch buffer in ArcGIS 10 . I don't know how can I buffer at once. Please help me. sincerely
5
votes
1answer
253 views

What is the width of the beach of a little island polygon?

This is a "classic" problem, that have no practical utility (see note-1 for applications), but illustrate another GIS problems... We can do some approximations to modeling the situation, the real ...
7
votes
3answers
622 views

Is there a st_buffer inverse function, that returns a width estimation?

When you supply a geometry g1 and a width w to the standard OGC function ST_Buffer, it returns a new geometry g2, g2 = ST_Buffer(g1,w) This question is about the inverse: a function where you ...
5
votes
2answers
226 views

Using newly created features in the next part of a python script

Good Afternoon I am trying to write a python script which buffers a large number of features from a geodatabase (but not all) and then dissolves the newly created buffer shapefiles together. ...
1
vote
3answers
985 views

In ArcMap, what is the difference between Copy Parallel and Buffer?

To build an offset of a linear feature in ArcMap, what is the difference between Copy Parallel and Buffer? In terms of the resulting features and their linear differences from the source linear ...
2
votes
1answer
665 views

Geotools // buffer using different CRS

I'm currently having a problem with Geotools. I try to generate a buffer (in meter using Lambert 72) on a map that has WGS84 as it's coordinatesystem. (problem is a bit like this one: ...
6
votes
1answer
2k views

ArcGIS: inside buffer with attributes?

How can I create buffers for polygons that a) lie only inside the polygon boundary, and b) know who their parent is? An example of where this is useful is First Nation Traditional Territories. There ...
6
votes
2answers
819 views

memory issue when trying to buffer/union large dataset using postgis

I am trying to generated a dissolved buffer of a large point dataset (Ideally 29 million points - Address data in Great-Britain, but I receive the data by chunks of 1 million points, so these could be ...
1
vote
1answer
701 views

How can I make a buffer with xxx meter by NetTopologySuite

I am very new in NetTopologySuite, I work with the coordinatesystem in WGS84 by lon/lat, with the NetTopologySuite. I found the Buffer function to create a buffer with a distance, but how can I make a ...
6
votes
1answer
424 views

How to generate non-merging buffers in QGIS?

I'm using QGIS to construct some fixed width buffers from a coastline shapefile. Is there a way to easily handle overlaps/ median lines? (I'm not sure if there's a particular term or phrase I should ...
0
votes
1answer
229 views

Buffer and Intersect differences

“What is the difference between ‘Select by location using a buffer or intersection’ and the ‘Buffer’ or ‘Intersect’ Analysis tools?
2
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0answers
398 views

Creating a Geodesic Polyline Buffer in OpenLayers

I have a feeling that the answer is going to be 'You can't do that without some very complex coding' but I thought I'd go for it anyway. I recently asked a question on how to create a Polyline Buffer ...
4
votes
2answers
5k views

Creating a Polyline Buffer in OpenLayers

I was wondering if there was a way to create a buffer around a polyline feature in OpenLayers. I have created a tool that allows the user to draw a circle buffer zone of whatever size and style they ...