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

learn more… | top users | synonyms

12
votes
1answer
11k 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 ...
8
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 ...
5
votes
1answer
766 views

Calculate population within radius

I have population data matched with polygons and a set of points that I have drawn buffers around. Assuming that the population within each geographical area, i.e. the polygons, is evenly distributed, ...
19
votes
4answers
20k 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
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 ...
6
votes
4answers
2k views

Improving 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 ...
7
votes
3answers
763 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 ...
4
votes
4answers
1k views

Creating polygons as % of original area using ArcGIS Desktop?

I have a polygon shapefile and need to create new polygons, within the originals, as % of original area. I used buffer by field (Field= new area as %) but the buffers are created in circles around ...
5
votes
6answers
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?
16
votes
4answers
4k 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 ...
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. ...
10
votes
2answers
6k 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 ...
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 ...
5
votes
1answer
276 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 ...
0
votes
2answers
395 views

Selecting isolated polygons which are not donuts but may overlap using ArcGIS Desktop?

I'm exploring a few different options for this process and I'm unsure what would be most effective. I'm trying to find all isolated, non-intercepting polygons in the same layer (not to merge). Most ...
15
votes
6answers
18k views

Performing reverse clip in ArcMap?

Is there a way to perform a 'reverse' of the clip function in ArcMap? I am not exactly sure how to explain this so here is a diagram:
5
votes
2answers
6k 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 ...
10
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 ...
8
votes
3answers
178 views

Creating buffer only in specific direction using ArcGIS for Desktop?

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
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 ...
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
1answer
5k 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 ...
4
votes
3answers
571 views

Buffering with physical barrier using ArcGIS for Desktop?

I don't think it 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 ...
4
votes
2answers
600 views

Getting buffer wizard-like speed in Python (vs using MultipleRingBuffer_analysis)

I've got a script that takes a single input polygon feature, throws 10 buffers around it at tenths of a specified input distance, and then symbolises the output based on an existing layer file. ...
3
votes
1answer
1k views

create polygons and fishnets of specific size and orientation and buffers

I want to study 6 areas in the field and in order to do so I want to divide each one of them into smaller areas/parts. What I would like to do is find an average square or rectangle area surface (...
0
votes
0answers
78 views

For every point create a wedge

How does one create a wedge polygon from a point? If I have 2000 points, I want each to have a wedge starting at each point with each point having a defined azimuth that the wedge points toward. That ...
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 ...
7
votes
2answers
4k 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 ...
4
votes
3answers
4k 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), ...
2
votes
2answers
398 views

Why does the buffer take up whole screen?

I am trying to create buffers around the Hurricane Sandy path I created in QGIS (points are lat/long). I have both points from each day she was tracted and the line I created from it with Points2One....
2
votes
2answers
350 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 ...
2
votes
1answer
547 views

Large Dataset Buffer Help

Using ArcGIS 10.1. I have a large polygon feature class (130,000 records). I need to do an inside/outside buffer (+5 then -5 to fill in some gaps)... the process takes so long, I'm looking for a way ...
1
vote
2answers
786 views

How can I calculate how many of a certain feature lie within my various buffer rings?

I am using ArcMap and I have a series of real estate parcels mapped along with a series of wind turbines. I have created multiple buffer rings around each real estate parcel with distances (0.5, 1, 1....
1
vote
1answer
36 views

Using negative radius buffer for ST_Buffer?

I am using postgis 2.2. I am using ST_Buffer to my polygon and it's working for positive radius (in meters) but when i am going to apply negative radius it is showing empty values. Here is my ...
6
votes
2answers
1k 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 ...
5
votes
1answer
10k 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
1answer
684 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 ...
2
votes
1answer
3k views

calculate the population inside a buffer with census data

I have population data matched with polygons and a set of points that I have drawn buffers around. Assuming that the population within each geographical area, i.e. the polygons, is evenly distributed, ...
2
votes
2answers
995 views

What's the best way to determine if a point is within a certain distance of a GEOJSON polygon?

What's the best way to determine if a point is within a certain distance of a GEOJSON polygon? Should one use TurfJS buffer method (https://github.com/Turfjs/turf-buffer#turf-buffer)? Can one perform ...
7
votes
1answer
1k 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 ...
5
votes
1answer
1k 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
114 views

Extracting Overlapping Parts of Single Polygon Layer using QGIS?

I have a single polygon layer with over 200 buffers with a lot of overlapping areas. I want to use QGIS to create a new layer representing the overlap. I've seen several questions that are similar, ...
2
votes
1answer
899 views

Remove overlapping buffers

I have put a buffer around points from a point data set. But some buffers overlap each other. Now I would like to remove all the buffers (from the data set) which overlap another buffer. Does ...
2
votes
0answers
166 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
2answers
294 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 ...
1
vote
1answer
630 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(..., ...
1
vote
2answers
2k views

How can I create a merged buffer in QGIS then count points that fall within it

I have a QGIS plan which shows ponds (as points in a shape file with an OS tile as a background) within a survey area. I need to calculate the total number of ponds within 1 km of each of the on-site ...
0
votes
6answers
5k 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
7
votes
2answers
774 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 ...
6
votes
3answers
101 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 buffer....