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

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12
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4answers
10k 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
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 ...
5
votes
1answer
468 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
230 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
743 views

ArcGIS Buffer accuracy problem

world, 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 ...
2
votes
1answer
164 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 ...
2
votes
1answer
239 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
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 ...
8
votes
2answers
2k 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
963 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
729 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 ...
5
votes
1answer
297 views

Geodesic buffers for polygons

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?
7
votes
1answer
5k 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 ...
3
votes
2answers
861 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
3answers
1k views

Is it possible to create 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
297 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
252 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
290 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
160 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
534 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 ...
0
votes
2answers
537 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
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?
1
vote
2answers
75 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
321 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 ...
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 ...
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 ...
1
vote
1answer
480 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
2k 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), ...
4
votes
1answer
381 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, ...
5
votes
2answers
305 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
3answers
1k views

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

I am very new to GIS, so go easy on me. 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 ...
5
votes
2answers
2k 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 ...
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 ...
4
votes
1answer
508 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 ...
2
votes
3answers
1k 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
1k 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 cant get my head around ...
3
votes
2answers
296 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
3k 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 ...
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
466 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
291 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 ...
0
votes
6answers
3k 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
3
votes
3answers
5k 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
712 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 ...
2
votes
0answers
313 views

Proximity Toolset Questions - Description, Examples of Usage, and Limitations

I was wondering if you could help me answer a few questions about the Proximity Toolset. I have been given the task of describing each tool in laymen terms, the typical usage of each tool, and most ...
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 ...
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 ...