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

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7
votes
3answers
428 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 ...
12
votes
3answers
3k 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 ...
5
votes
2answers
300 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
2k views

ArcGIS: inside buffer with attributes?

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. There ...
5
votes
1answer
192 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 ...
5
votes
1answer
3k views

What is up with 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
3answers
6k views

Creating a square buffer around a point feature in ArcMap

I would like to create a square buffer from a point feature. I do not understand the code that gos into it. This similar questions as asked on the forums.esri website but that was over 10 years ago. ...
2
votes
2answers
3k 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 ...
4
votes
1answer
217 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
3answers
819 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.
7
votes
2answers
422 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
638 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 ...
7
votes
2answers
1k views

Create “Inner Buffer” in ArcGIS

I am currently searching for a possibility to create an "Inner Buffer" in ArcGIS. I have a lot of polygons (houses)(in one feature class) and one big polygon (in one other feature class). I want so ...
5
votes
1answer
998 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 ...
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), ...
3
votes
3answers
276 views

Buffer with physical barrier

I don't think 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 larger ...
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 ...
1
vote
2answers
228 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 ...
9
votes
4answers
1k 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 ...
5
votes
4answers
2k views

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 ...
4
votes
2answers
1k 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?
3
votes
3answers
186 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 ...
3
votes
2answers
257 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 ...
2
votes
2answers
177 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
312 views

How to set linear units for Buffer distance from arcpy.GetParametersAsText()?

I am trying to run a buffer tool as part of script that I will both use as a standalone script and import into ArcToolbox. I'm just wondering, if I use GetParametersAsText for the buffer distance, how ...
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 ...
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 ...
1
vote
1answer
50 views

Select point with highest value within a buffer

I work with ArcMap 10.2.1 and I created buffers around points. Some buffers contain many points and others just one. I would like to select one point for each buffer, but the points can represent ...
1
vote
1answer
52 views

Buffer Zip Region Polygon with GeoTools

What I want to achieve is to buffer a zip region geometry with a distance in meters and than get the coordinates of the new (expanded) polygon. The original geometry polygon is parsed from a kml file. ...
1
vote
1answer
197 views

How to fit a polygon to a “best buffer” about a reference geometry in it?

If I have a polygonal geometry gbase, like a street (a rectangular strip), and a reference geometry gref, like a central line of gbase. The question is what is the function (here named BestBuffer) ...
1
vote
1answer
420 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 ...
1
vote
2answers
1k views

“Item not found in this collection” when trying to set the Shape on IFeatureBuffer

I'm working on code to open a 3rd party data file and convert it into a collection of features in a custom layer based on FeatureLayer. I have had no issue importing the data itself (nodal data for ...
0
votes
2answers
81 views

Low resolution raster conversions to vector yielding millions of single pixel polygons. Trying to merge all directly adjacent polygons

I'm trying to scan plain pdf maps containing color-coded geographic regions and convert them into undifferentiated (I don't actually need them to contain any attribute data) overlays. My workflow is ...
0
votes
1answer
142 views

Sum of values within a buffer polygon

I need to do the following in QGIS and hope so much anyone could help. I have a vector layer with points. Each point represents a firm with the number of employees in the attribute table. I want to ...