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

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2answers
2k 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?
4
votes
2answers
405 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 ...
4
votes
1answer
270 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?
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 ...
4
votes
2answers
209 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 ...
4
votes
4answers
506 views

ArcGis 10 - create polygons as % of original

Could someone help me with the following? 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 ...
4
votes
2answers
337 views

How to extract values from intersection of different size buffers with raster?

I have a polygon shape with buffers. However, the buffers are of different size from 4m radius to 15m. In total I have 7 different buffers. I have a landcover raster and I would like to extract ...
4
votes
2answers
1k views

How to invert a Buffer(get the inside of a ring buffer)?

I have a line layer of a road network around which I create a buffer zone of 1000 m with Analysis Tools>Proximity>Buffer. But I am interested in the areas outside the buffer zone, and not the buffer ...
4
votes
1answer
154 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, ...
4
votes
1answer
278 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 ...
4
votes
1answer
293 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 ...
4
votes
1answer
84 views

Buffering Points Directionally

I have about 10,000 points that I want to apply a partial circular buffer to based on an angle, from -30 to 135°. A similar question for polygons seems to have been answered here, but I cannot make ...
4
votes
3answers
214 views

How to compute the outline of multiple tracks?

I have multiple gps tracks with depth data gathered from the lake. The tracks are overlapping/intersecting. I want to get an outline polygon. I have a multi-line shp. I've tried to diffuse it in qgis ...
4
votes
2answers
470 views

How to delimit hinterland boundaries among multiple city centers?

I need to delimit city boundaries basing on centers'magnitude. CenterA's employment/CenterB's employment = (Distance from centerA to break-point E/Distance from centerB to break-point E)^2. AB=AE+BE. ...
4
votes
2answers
406 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. ...
4
votes
1answer
403 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, ...
4
votes
1answer
304 views

How to create a buffer on a linestring with varying or increasing/decreasing width

I want to buffer rivers/streams for a topographic map. I'm using a PostgreSQL/PostGIS database. Usually, I create buffer with ST_Buffer with a constant width. For example, the width of a river buffer ...
4
votes
1answer
277 views

How to maintain right-angles when buffering?

When buffering some polygons I am trying to avoid the curved buffered area like this: I'm trying to do thins within an FME workbench but if someone knows how its done in other software that would ...
4
votes
1answer
92 views

Problems with Buffer tool. Looking for help please

I am trying to create a buffer around different series of lines. I have a polylines file with 1 location shown below: I want an equal spaced buffer that is dissolved around all the lines at this ...
4
votes
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 ...
4
votes
3answers
765 views

How to join number of point features into attribute of nearest line segment using ArcGIS Desktop?

I have point shapefile with lot of attributes, that represent road accidents and line shapefile with highways. What i want is to join attribute into line shapefile with value, that represent number of ...
4
votes
0answers
433 views

How to create multi-ring buffers automatically in QGIS? [duplicate]

I'm wondering if anyone knows of a tool or plugin for QGIS that allows for multi-ring buffers. I've found a post about doing multiple buffers one by one, but was hoping there was a way to do this all ...
4
votes
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), ...
3
votes
2answers
236 views

Buffer Polygon, BUT Inside and Only for a Distance

There has to be an easy way to do this. Been plugging away for an hour and I don't know if I am brain dead or what. What I need to do is buffer a polygon on the inside, but only for 500 metres. If ...
3
votes
2answers
954 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 ...
3
votes
2answers
337 views

Performing 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 ...
3
votes
2answers
2k views

How can I use the Buffer Wizard in Modelbuilder or arcpy? (ArcMap 10)

I am creating a model in ArcMap 10 and I need to use the Buffer Wizard tool to create multiple buffers within a polygon feature class. The problem is, I can't seem to place the Buffer Wizard within my ...
3
votes
2answers
125 views

Create a buffer with a pre-defined area?

I have a road (line) system and need to create a polygon from it to show the right-of-way area. The right-of-way area is calculated in the field from taking measurements from the road centreline. From ...
3
votes
2answers
522 views

Creating square buffer in qgis

How can I create a buffer with square ends along a line segment in qgis? I've buffered lines using v.buffer in the GRASS plugin, but the -c option for square ends is not exposed in that interface. ...
3
votes
2answers
415 views

Need Projection Help to Buffer Lines in QGIS

I am somewhat new to GIS in general, and very new to QGIS specifically (I took one class and we used Arc, which I don't have access to any more). I need to create buffers (1km, 3km, and 5km) around ...
3
votes
1answer
3k views

creating a buffer in a raster layer

I've got a raster layer separated into 3 zones, representative of marine park zones. What i'm trying to do is make it so that where zone 1 is adjacent to zone 3, there is a "buffer" between them, of ...
3
votes
2answers
2k views

How to Hide InfoWindow/Popup when “no information available” or when buffering?

I have an app that does some buffering, only problem is when I click on the map to put in the point/line/polygon vertices to do the buffer, I get popups at every mouseclick. It doesn't interrupt the ...
3
votes
3answers
6k 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 ...
3
votes
1answer
2k 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
108 views

PostGIS Nearest Neighbour outside buffer

I am trying to find the 6 nearest neighbours to a point which are outside a defined buffer. Basically I am comparing points of the same table and working with Mike Gleason's examples. WITH subq AS ...
3
votes
1answer
253 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 ...
3
votes
1answer
636 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 ...
3
votes
1answer
3k 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
1answer
1k 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 ...
3
votes
1answer
142 views

How to create a cluster of crashes?

I have a shapefile with 52K points of road accidents, between 2007 and 2012. Each accident has a severity index. I want show clusters of 5 accidents (at least), for each year, that have a severity ...
3
votes
2answers
101 views

Clipping multipart polygons iteratively

I have a shapefile of buffers (n=10) and a shapefile of watersheds (n=10). Both shapefile contain overlapping features. I would like to clip each watershed feature with it's corresponding buffer, ...
3
votes
2answers
578 views

How to do a Point to Polygon analysis with multiple variables?

I have a database of almost 10k crimes, which are divided in to 10 categories and plotted on a map I also have a database of 12k addresses, which are also plotted on the map. I aim to perform a ...
3
votes
1answer
1k 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 ...
3
votes
1answer
298 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 ...
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 ...
3
votes
1answer
649 views

datum conflict when creating buffer in arcgis 10

A buffer I created successfully executed, but I received the following message: "WARNING 000632: Datum conflict between map and output." How can I fix this?
3
votes
1answer
39 views

Extending buffer zone

I am working in ArcMap 10.2 (and Modelbuilder) and I would like to solve the following problem: I have Buffer A (single part) and Buffer B (multipart). I would like to extend Buffer A with Buffer B ...
3
votes
1answer
779 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 ...
3
votes
1answer
345 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 ...
3
votes
2answers
2k 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 ...