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

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2
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1answer
461 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: ...
10
votes
2answers
972 views

How to buffer a line with different distances for left/right sides

How can I buffer a line in QGIS using one attribute for the left side of the line and one attribute for the right side of the line? I am trying to buffer a river with its bank width, which is ...
5
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 ...
4
votes
2answers
532 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 ...
0
votes
1answer
489 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
328 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
180 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
votes
0answers
299 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 ...
3
votes
2answers
3k 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 ...
3
votes
1answer
2k views

How to create a polygon (fixed width buffer) around a polygon in QGIS?

I have created a polygon in QGIS (in this case it describes a country's maritime baseline). I need to create a second polygon whose boundary is a fixed distance from the original polygon. (in this ...
3
votes
3answers
308 views

Buffer with physical barrier

I don't think is possible, but I'm looking for a way to stop my buffer at a certain physical barrier. For example, I have point near a river and I'm creating a buffer around my point that is larger ...
3
votes
1answer
272 views

How to calculate buffer surface that falls within another layer's borders

The image below shows what two selected layers. One contains a series of borders, and the other a series of buffers. I am trying to obtain the buffered surface within each of the borders in the ...
4
votes
1answer
235 views

Surface covered by buffers in QGIS

In QGIS, I have plotted buffers around points. I would like to calculate the area which falls under buffers without over counting due to buffer overlaps. Is there a quick and easy way to do this?
7
votes
2answers
729 views

Growing a PostGIS geometry by a percentage

I'm looking for a way to add a buffer around a PostGIS geometry, but the size of the buffer should depend on size of the geometry. That is, I want each geometry to be enlargened by, say, 5%. The idea ...
1
vote
1answer
345 views

how can i use flat buffer for polygon?

i'd like to create flat buffer in a polygon shapefile .i try to use buffer tool in ArcGIS 9.3 but i could'nt select "flat" option in endtype combobox because the input feature is polygon .how can i ...
2
votes
2answers
1k views

polygons won't buffer in ArcMap

I have been trying to buffer 15 polygons (-15m) in ArcMap. I did a batch buffer and 13 polygons worked fine, the other 2 have not buffered, an error occurs: WARNING 000117: Warning empty output ...
4
votes
1answer
354 views

automating forest cover calculations with Python

I have a layer of forest cover comprising ~ 30,000 individual forest patches, and I need to calculate the amount of forest cover within a 5 km buffer of each patch. The buffers all overlap each other, ...
3
votes
2answers
763 views

Generate non-overlapping shapes from a buffer

I have a collection of points, and I need to generate shapes around these points. Let's assume that these points are locations of offices and that the shapes are the 'area of responsibility' around ...
2
votes
1answer
213 views

Query for segments at same place and time in PostGIS

A newbie-question: I've imported the segments of several GPX-Tracks in a PostGIS-Table. Now I'm looking for a query that returns all segments that: are spatially overlapping (within a specific ...
2
votes
1answer
149 views

Overlapping buffers - Doublecount points that fall within 2 or more buffers

I want to analyze crime around certain types of stores in a city. I made buffers around the stores and I need to a) select and extract crimes that occurred within those buffers, and b) join the two ...
4
votes
1answer
2k views

Best way to get Convex Hull/Boundary of millions of points

I've been trying to do some point analysis on some xyz data, I'm at the point where I've decided it is best to produce a boundary of my xyz files and put this with the metadata for each survey. Now ...
3
votes
1answer
804 views

How to obtain statistics within a Buffer/Catchment in MapInfo?

I need to calculate the population statistics within a 10 minute drivetime catchment from a point and within 1 Km Buffer from a point in MapInfo, how can I do that can someone please elaborate? I have ...
2
votes
1answer
218 views

how to extract overlap from non-dissolved buffer zones in qgis 1.7.4

I have a shapefile with the inventory of all limetree in a region. I made a buffer around each tree. So, the place where buffers overlap each other is the best place to put beehives. Is there a way ...
3
votes
2answers
1k views

ArcGIS 10: How to clip point buffer to features in another layer?

I'm on a steep learnig curve here, so aplogies if my question is a one-banana problem. In ArcGIS 10 I have a contour layer that was generated from an ESR ASCII raster file (batyhmetry of the South ...
7
votes
2answers
2k views

Create “Inner Buffer” in ArcGIS

I am currently searching for a possibility to create an "Inner Buffer" in ArcGIS. I have a lot of polygons (houses)(in one feature class) and one big polygon (in one other feature class). I want so ...
5
votes
2answers
649 views

Create a polyline buffer with Arcpy

I'm trying to write a python script with ArcPy that draws arcs and I've achieved something with creating a buffer and then clipping it with a bounding box so I only keep the length I need (I thought ...
0
votes
1answer
277 views

Generate a report or table for buffer zone

I have a polygon feature class. I create a buffer for this feature with a distance being 2 km.Now the buffer output intersect with features of the original polygon.So say for instance from the orginal ...
1
vote
2answers
238 views

Buffer point dataset based on compared value

I am creating polygons from the dissolved buffers of points and need to control the dissolve process. In the model the first stage is to assign high/med/blackspot using the following f2='ERROR' def ...
3
votes
1answer
283 views

ArcMap: extracting overlapped buffers

I have a set of points in ArcMap which I create a buffer for each point. Then I use intersect to extract the overlapping buffers. The result is something like this: The lighter color are the ...
2
votes
2answers
155 views

After two buffers operations (+/-), why is the result file bigger than the original?

First file ( .shp ) had 1000KB, after 2buffers ( buffers on polygon, 1st buffer +100, 2nd buffer -100 ( small things near polygon should be removed )) in quantum gis file grown to 1500KB, and after ...
1
vote
1answer
459 views

Converting distance between nautical miles and degrees

This is such a basic question that I'm kinda of embarassed. Here is the situation: We have a certain funcionality developed that: Will check for a tolerance value (this input is given by the user ...
4
votes
2answers
1k views

Multiple ring buffer with attributes

Building on ArcGIS: inside buffer with attributes?, I'd like to be able to create multiple ring buffers, while retaining (and possibly dissolving on) attribute values. How can this be done?
2
votes
2answers
418 views

Buffer in ArcGIS v. ArcINFO 9.3

I have ArcGIS 9.3 and my question is regarding Buffering. Is that only allowed in ArcINFO or is there a way to use a buffer in ArcGIS?
1
vote
1answer
302 views

Best practices to minimize error when buffering unprojected data

If I buffer hundreds of unprojected WGS84 points across the US by say, 3 miles, will I get accurate areas returned (3 x pi x r) for each of the circles created? I suspect not. If not, what would be ...
1
vote
1answer
456 views

How to use buffers to estimate the attribute data for a given polygon?

I have two layers: point and a polygon. The point layer has lat/long and I have created buffers of a 1/4 mile. The polygon layer has data such as age and income. Is there a plug-in that can ...
3
votes
1answer
1k views

How to Buffer with intersections in QGIS

I am buffering a layer of facilities (points). I will then use the buffer to clip and intersect another layer, containing resources. I want to answer the question, how much of the resource lies ...
3
votes
1answer
880 views

Buffer Selected Line Segments Using ArcGIS 10 or Python

I haven't quite found a solution for buffering selected line segments of a road network without extporting the selected line segments to a new file and then buffering. I want to avoid creating a ...
5
votes
1answer
1k views

How to calculate the size of a particular area below a buffer in QGIS

I have a point shapefile of villages where data was collected in Northern Kenya. I created a buffer around those villages. The second vector layer contains polygons defining areas according to ...
5
votes
2answers
1k views

Need help calculating forest cover within a buffer when it overlaps with other buffers

I'm new to ArcGIS and having real trouble getting this done… Hopefully someone can help. Thanks in advance! I have a layer showing forest cover in a landscape. I'm trying to create a 5km buffer ...
5
votes
2answers
287 views

How can I create a “setback” buffer in QGIS?

I've been going a bit crazy in trying to create a "setback" buffer on QGIS for coastal lines in a map projecting this buffer outwards towards the sea. I've managed to create a normal Bidirectional ...
2
votes
1answer
2k views

ArcGIS10 - How do I dissolve two different buffers together so they are not overlapping?

I am trying to find out how many registered sex offenders live within 2,000 feet of a school/park in a specific county. The park buffer and school buffer are dissolved but not together. I am also ...
5
votes
3answers
2k views

When should I use ST_Buffer?

I would like to know what is the sense of using st_buffer operation. In PostGIS reference guide there is only the syntax and a short description of this operation. Could you give some examples to ...
3
votes
1answer
431 views

QGIS inside buffer with attributes

Fairly similar to ArcGIS: inside buffer with attributes? but in QGIS. It would be convenient if the buffer layer inherited the attributes of the parent. Also I am doing inside buffers (-ve distance ...
3
votes
2answers
274 views

Is there a way of doing a statistical analysis of buffers?

I am doing a buffer analysis of incinerators and looking at the output areas within those buffers, is there a way of doing a statistical analysis of several buffers to see if there is a significant ...
7
votes
3answers
1k views

Use buffer tool to draw different radii?

I am new to Arcmap-Arceditor 10 and could really use your help. I have been mapping ethanol plants (which utilize corn to produce ethanol) and corn production amounts in the counties of the USA. ...
5
votes
3answers
1k views

How can I display with OpenLayers the geometry returned from a ST_Buffer in POSTGIS?

Im using PostGIS, GeoServer and OpenLayers, and the thing is that i want to display the geometry result from a query like this: SELECT ST_Buffer(ST_GeomFromText('POINT(100 100)'), 500); To perform ...
0
votes
2answers
463 views

how do you do a buffer analysis of a geographical location?

I want to use a buffer analysis to identify the geodemographics of Incinerators. I have downloaded the Output Area Classification (OAC) map and also know the locations of all the Incinerators I want ...
4
votes
1answer
287 views

Select points within 2 buffers

I have 2 huge files of points (hundreds of thousands of points). I need to determine a way to loop through all the points in one file and find all the points in the second file that are only a ...
3
votes
3answers
4k views

How to create a polygon buffer from a line?

I have connected a series of points into a line in ArcMap 10 with the Points to Line tool in the ArcToolbox. The line is, of course, in its own layer, and I added a 5 meter buffer around the line. It ...
1
vote
2answers
684 views

Error adding buffer to polyline in ArcMap 10

As the next step to what I did in this previous question, I would like to add a buffer to a polyline, with 5 meters on either side. I tried adding buffer to two versions of the line, one in ...