Questions tagged [buffer]

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

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31
votes
6answers
34k 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 ...
2
votes
2answers
4k views

Polygons will not buffer in ArcMap and instead give WARNING 000117: Warning empty output generated?

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 ...
5
votes
1answer
2k 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 ...
2
votes
1answer
369 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 ...
13
votes
2answers
1k 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. ...
3
votes
1answer
231 views

OveDouble counting points that fall within 2 or more overlapping buffers in ArcGIS Desktop?

I want to analyze crime around certain types of stores in a city. I made buffers around the stores and I need to: select and extract crimes that occurred within those buffers, and join the two ...
4
votes
1answer
5k 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
2answers
564 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
3k 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 ...
14
votes
2answers
15k 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 ...
3
votes
1answer
2k 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 ...
5
votes
2answers
1k 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
457 views

Geodesic buffers for polygons in ArcObjects?

How can I create geodesic buffers around polygons? I'm on 9.3.1 ArcMap, but I need a programatic solution. IBUfferConstruction only does geodesic buffers for points. What are my options?
23
votes
1answer
24k 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 ...
4
votes
2answers
2k 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 ...
8
votes
6answers
7k 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?
0
votes
1answer
385 views

Generating report or table for buffer zone using ArcGIS Desktop?

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 ...
1
vote
2answers
313 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
389 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
170 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
996 views

Converting distance between nautical miles and degrees using ArcObjects?

We have a certain functionality developed that: Will check for a tolerance value (this input is given by the user as NM); Buffer a polygon by that value (all polygons are in WGS-84); Iterate through ...
0
votes
2answers
1k 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.
4
votes
2answers
3k views

Multiple ring buffer with attributes

Building on Inside buffer with attributes in ArcGIS?, I'd like to be able to create multiple ring buffers, while retaining (and possibly dissolving on) attribute values. How can this be done?
3
votes
3answers
3k views

IFeatureBuffer - performance considerations (ArcObjects)

I'm trying to optimize my code to make it faster. I have a loop that reads some string input and creates points with the help of IFeatureBuffer and IFeatureCursor. If I create the buffer inside tho ...
1
vote
2answers
90 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 ...
1
vote
1answer
461 views

Minimizing error when buffering unprojected data in ArcGIS Desktop?

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 ...
3
votes
1answer
2k 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 ...
7
votes
1answer
4k views

Calculating size of particular area below 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 ...
1
vote
1answer
662 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 ...
4
votes
3answers
6k views

Conflicting measurement units with buffer ftools [duplicate]

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), ...
4
votes
1answer
502 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, ...
6
votes
3answers
755 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 ...
3
votes
4answers
5k views

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

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 the general steps for what i am doing: ...
6
votes
1answer
3k views

Calculating forest cover within buffer that overlaps with other buffers?

I'm new to ArcGIS. I have a layer showing forest cover in a landscape. I'm trying to create a 5km buffer around every forest patch in the landscape and then calculate the amount of forest within ...
2
votes
1answer
6k views

Dissolving two different buffers together so not overlapping using ArcGIS Desktop?

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 ...
8
votes
3answers
6k 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
1answer
3k views

QGIS inside buffer with attributes

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

How to find most common classification within buffers?

I have a point shapefile that identifies the location of incinerators in England and an output area classification shapefile. I have created a buffer for all the points in the shapefile because i ...
2
votes
1answer
2k views

ArcGIS Server js API - buffer query against polygons and not points

I'm using the below sample and I want to change the queried results from points to polygons http://help.arcgis.com/en/webapi/jav...ry_buffer.html Probably very simple but can't get my head around ...
3
votes
2answers
530 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 ...
5
votes
2answers
10k 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 ...
8
votes
3answers
2k 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. My ...
5
votes
3answers
2k views

Displaying geometry returned from ST_Buffer in PostGIS with OpenLayers?

I'm 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
494 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
336 views

Selecting 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 ...
0
votes
6answers
6k views

Batch buffer with Python in ArcGIS 10

I have some feature classes (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.
3
votes
2answers
13k 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
971 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 ...
5
votes
1answer
3k views

Understanding why buffers not circular in QGIS?

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 them ...
3
votes
1answer
3k 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 ...