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

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24
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6answers
1k views

How to buffer raster pixels by their values?

The pixels to the left represent tree locations and their associated crown radii (i.e. pixel values ranging from 2 - 5). I would like to buffer these raster pixels by their crown radius value. The ...
18
votes
4answers
17k views

Creating square buffer around point feature using ArcGIS for Desktop?

I would like to create a square buffer from a point feature but I do not understand the code that goes into it. Similar questions have been asked on the forums.esri website but that was over 10 ...
15
votes
4answers
3k 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 ...
14
votes
4answers
2k views

Is there Python library (other than ArcPy) for geoprocessing such as buffer?

Excluding ArcPy, is there any python library which can do geoprocessing, such as buffer/intersect, with shapefiles?
14
votes
5answers
13k views

Performing a reverse clip in ArcMap?

Is there a way to perform a 'reverse' of the clip function in ArcMap, I'm not exactly sure how to explain this so here's a diagram:
14
votes
4answers
4k views

How to create one-sided buffers or parallel lines in PostGIS?

I'm looking for a way to create so-called one-sided buffers or parallel lines in PostGIS. Example: 1. buffer, 2. one-side, 3. both-sides I've found some discussion on the mailing list from 2009 and ...
13
votes
2answers
973 views

ArcGIS Buffer accuracy problem?

Once again I encounter something very strange with ArcGIS. I perform a buffer analysis on one side of a polyline. There seems to be a serious accuracy problem and I can't figure out what the cause is. ...
12
votes
5answers
894 views

Simulating the expansion of polygon features

I've got what I'm hoping will be an interesting question. I'm working on an assignment for an intro to GIS course that uses some Gulf oil spill data to introduce common vector-based spatial analysis ...
12
votes
2answers
2k 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 ...
10
votes
2answers
5k views

Creating “Inner Buffer” using ArcGIS for Desktop?

I am currently searching for how to create an "Inner Buffer" in ArcGIS for Desktop? I have a lot of polygons (houses) in one feature class, and one big polygon (in another feature class). I want so ...
10
votes
1answer
9k views

Understanding QGIS buffer tool units?

I have been trying to figure this out for a couple weeks now and have had no luck getting the buffer tool to accept anything but degrees as units of measure. I have found lots of stuff saying the ...
9
votes
2answers
362 views

Create area buffers that are limited by a coastline

I'm trying to use ArcGIS 10.2 to create a buffer of points based on a pre-defined area (e.g 400 sq km). Further to that, the buffers of some of the points are close to the coastline that requires the ...
9
votes
1answer
296 views

Proximity in space and time

I have some point data which represent daily lat-lon locations of an animal, with an associated timestamp. I would like to identify all points where STATIONARY = TRUE. A point qualifies as being ...
9
votes
2answers
1k 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 ...
9
votes
2answers
3k views

How can you tell if ArcCatalog Geoprocessing is still running?

Is there some other way other than the logs to check that ongoing geoprocessing is working correctly? I am running the Buffer tool with dissolve type ALL on ArcCatalog 10.1. I was expecting the the ...
8
votes
2answers
2k views

projection change to create buffer in QGIS

I am about to become desperate... I like to create buffer around several points - if possible - with a declaration of the size in km of these buffers. Just to show you what I am working with: My ...
8
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. ...
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 ...
7
votes
3answers
4k 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 ...
7
votes
2answers
1k views

How to create an oriented buffer using arcpy?

I would like to create an oriented buffer for every polygon in my shapefile using arcpy. By oriented I mean that I have two angles a1 and a2 that constraint the direction of the buffer. This is ...
7
votes
2answers
3k 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 ...
7
votes
3answers
117 views

How to set a buffer only in a specific direction?

I am trying to create a buffer for several polygons in a south-western orientation. As far as I know, this is not possible using the buffer tool (I use ArcGIS 10.3). I could do it manually but for ...
7
votes
1answer
2k views

Inside buffer with attributes in ArcGIS?

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. ...
7
votes
2answers
70 views

Creating a point on edge of closest polygon

My project is looking at a grid in the ocean. I want to capture each ocean point's distance to the nearest coastline as a weight, and then use buffer to capture the sum of nightlight data within a 1 ...
7
votes
1answer
843 views

Is there a significantly faster way to buffer than arcmap? [duplicate]

I hope this question is appropriate here and I apologize if it is more of a discussion question than a specific technical problem. I have to buffer 150,000 polygons for a real estate project. While ...
7
votes
3answers
716 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 ...
7
votes
1answer
325 views

How can I conduct Geographically Weighted Analysis using an exponential decay function?

I have some points (representing 30 study sites) and I want to calculate the weighted mean of several variables (landscape layers) using a negative exponential decay (weights function) to give more ...
6
votes
3answers
78 views

Select all polygons that are completely within a circular buffer

I made several buffers around some points. Now I want to select all polygons that are completely within this buffer. My problem is that I also get the polygons that are partially outside of the ...
6
votes
1answer
2k 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 ...
6
votes
1answer
703 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 ...
6
votes
2answers
984 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 ...
6
votes
1answer
478 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 ...
5
votes
4answers
2k views

How to improve upon ArcGIS Buffer/Dissolve performance?

I'm wondering if anyone else has experienced significant performance penalties when using the ArcGIS buffer function with the 'dissolve' option on point features. My dataset is a shapefile of 260 ...
5
votes
2answers
491 views

How do the equations/algorithms behind buffering tools actually work?

I've been wondering how the equations/algorithms behind buffering tools actually work?
5
votes
3answers
933 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 ...
5
votes
5answers
2k views

Creating multiple buffers using QGIS?

I'm new to QGIS and have no programming skills. Is there an easy/uncomplicated way to create multiple buffers around a line feature?
5
votes
3answers
2k views

Create buffer around point in LeafletJS?

I am using LeafletJS. I want to create buffer around point. after Selecting a point buffer radius will be specifed by user in feet. After searching of awhile I found this link of JSTS. does JSTS ...
5
votes
1answer
6k views

QGIS - Create buffer in meters

I'm very new to the GIS world, so my problem could be very stupid, but I'm going to try anyway. Objective Given a list of coordinates in longitude/latitude, stored as a .csv file, I want to create a ...
5
votes
2answers
1k views

Compound variables in Model Builder?

I'm trying to create a model wherein one of the parameters is a compound variable, that is made of multiple variables joined together. How can this be done? For example: create an insider buffer ...
5
votes
3answers
3k views

Dissolving polygons by attribute within certain distance using ArcGIS Desktop?

In a FeatureClass I have a lot of polygons which contain attributes of different landuse-types. Now I am trying to dissolve those polygons of the same landuse-type, but only if the distance between ...
5
votes
2answers
248 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. ...
5
votes
3answers
395 views

How can I create a “setback” buffer for coastal lines 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 ...
5
votes
3answers
2k 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 ...
5
votes
1answer
235 views

Cutting a circular buffer via Arcpy

I am currently working with compressor stations on centerline routes. These compressor stations have a 3 mile buffer surrounding them. I wish to cut a portion of the circular buffer off. These cut ...
5
votes
2answers
915 views

Creating 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 ...
5
votes
1answer
2k views

Why are my buffers not circular?

I would like to select areas under a particular circular radius in QGis. I believe this is accomplished with the buffer tool, but when I specify the radius the area is not circular. How to make it ...
5
votes
2answers
576 views

How to achieve “Flat-End” line buffers in QGIS?

I need to buffer a series of lines by 40m, however I only want the buffer to come off the sides and not off either end of the line. I know in ArcGIS there is a "flat-ends" tickbox that achieves ...
5
votes
1answer
4k 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 ...
5
votes
1answer
745 views

What is the unit of measurement for buffer calculation?

What is the unit of measurement used by Geometry class for it's buffer calculation ? Api doc currently defines it as " distance - the width of the buffer (may be positive, negative or 0)" I need to ...
5
votes
1answer
271 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 ...