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

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3
votes
1answer
189 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 ...
1
vote
1answer
110 views

What is the minimum buffer zone to get a certain amount of points within the zone?

I have one map with lines and another map with points. I want to find the distance of the buffer zone to be such so the amount of points that are in the buffer zone to reach a certain number. For ...
2
votes
1answer
282 views

Python add-in won't buffer from output layer

I have a simple add-in script for Arcmap 10.1 to create a toolbar, select a layer from a drop down list of the current layers in the project, buffer that layer four-miles, then use the resulting ...
-1
votes
1answer
46 views

ST_buffer display creates big circle [closed]

$result = pg_query("SELECT ST_Astext(ST_Buffer(ST_GeomFromText('POINT( 80.7605 7.67833 )'),1))"); ST_buffer display creates big circle..
2
votes
1answer
131 views

Buffers with Varying Distances around a Set of Points

I have set of points in one shapefile and I have a table with a unique identifier that matches each point. I want to make a buffer around each point, according to the radius that I have specified in ...
1
vote
1answer
47 views

Buffer from Field using Different Unit

Is it possible to create a buffer polygon using an attribute field which is in different units than the feature class coordinate system? Example: I have a field that stores distances in miles (double ...
2
votes
1answer
25 views

Applying distance/area dependent procedures in geographic coordinates over large areas?

I'm currently doing some niche modelling with data in geographic coordinates spanning all of Latin America. I am using R for my analysis. Some of the tasks I have to perform are area/distance ...
1
vote
0answers
42 views

How to calculate the area of overlapping buffers within a single layer

I am very new to GIS, so don't know if this is EXTREMELY easy or impossible. I have GPS coordinates for stores (about 15000) for which I have created a buffer zone around each store location ...
1
vote
2answers
103 views

How to split a (road) buffer using the centerline?

I have a road centreline dataset which I have buffered using the road width. I used the standard QGIS buffer tool. I realise for my analysis I actually need to split the road buffer in half and ...
0
votes
1answer
50 views

WFS Filter Buffer around a point

I'm trying to make a buffer around a geometry (point/s,linestring,etc) using WFS queries without luck. This is what I've been doing: <ogc:Filter> ... <ogc:Function ...
2
votes
1answer
42 views

How to do the overlap detect for buffered lines

We have almost 50000+ lines which we want to remove a line if it is too close to the other. So we tried to do a buffer for two line, then check if the buffer area are overlapped. I wonder if there ...
0
votes
1answer
61 views

QGIS convert polyline to fixed width polygon

I have a shp file of polylines for trails, and I need to convert them all to be polygons that are 8 ft wide (4 ft from the center of each side of the polyline). I tried a following a few other posts ...
0
votes
0answers
52 views

Is it possible to use custom (non-circle) buffer shapes?

I have a shapefile containing points. I'd like to replace each point by the same shape, centered around the point, like the "Buffer" tool with shapes other than circles. How can I do that?
2
votes
1answer
152 views

How to load a memory layer into map canvas an zoom to it with pyQGIS?

I would like to load a vector memory layer into the map canvas with pyQGIS. Background is, I create a memory buffer layer around point data. While iterating the points I would like to visualize the ...
1
vote
2answers
695 views

QGIS - Continuous buffer image [Heat Map]

Is it possible to have the representation like the one the heat-map like the figure below using QGIS? The way seems to use buffer options, but I do not know how. Does exist any plugin that helps? I am ...
0
votes
0answers
38 views

v.buffer angular buffer doesn't take all the polygons into account

I am trying to create an angular buffer around building footprints with the v.buffer command (QGIS 2.2). There is no error message, but the algorithm doesn't take into account all the buildings. This ...
1
vote
3answers
94 views

Create buffer in Metres

I want to create a buffer in meters around points in Europe. But I cannot find a proper CRS for Europe that is in meters instead of degrees?
1
vote
0answers
56 views

How to Buffer with Dissolve ALL on very large polyline dataset? [duplicate]

So I have a fairly large polyline network covering a decent chunk of North America, containing just shy of 900,000 table records. I want to do some very simple "GIS 101" kind of processing to it -- I ...
0
votes
1answer
58 views

Using the buffer tool in ArcGIS 10

I have a map that has a 12 mile buffer round it already. I have created a buffer inside the original 12 mile line (using a negative value of 9). Is it possible however to stipulate that the new buffer ...
0
votes
1answer
67 views

Generating buffers in a automate way

I would like to creat buffers in a automate form and no matter the way (e.g. script, batches and etc) I am asking if anybody here knows how to do it or if are there scripts ready to do it. My ...
0
votes
0answers
42 views

Creating multiples buffers (or rings)

I would like know how could I creat and automate with a batch multiples buffers (or rings) between two cut buffers where is crossing roads. I creat rings using the attribute table but I can't ...
0
votes
2answers
100 views

isolated polygons selection (not donuts)

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 ...
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.
1
vote
2answers
204 views

Sql Query for percent of buffer filled with objects

Hi I am trying to write a query to find the percentage of a buffer polygon (Called 250_Buffer) that is filled with or contains other polygons in another layer (Called Development) any help that you ...
0
votes
1answer
48 views

Find Minimum Value of Point within a buffer output as a point file

I have a series of 30m buffers along a polyline (river). Within each buffer I have a series of points each point represents a 10m x 10m cell with an elevation value known as "Elev". I want to find ...
-1
votes
1answer
47 views

Esri ArcGIS 10 - using ArcPy to select buffer line by length

I created a buffer, then converted polygon to line (around a city block). I want to select the internal line. I'm thinking since there is no uniform way that ArcGIS labels the interior or exterior ...
8
votes
5answers
2k views

Performing a reverse clip in ArcMap?

Is there a way to perform a 'reverse' of the clip function in ArcMap, I'm not exactly sure how to explain this so here's a diagram:
0
votes
1answer
102 views

batch buffer with different distances with python 2.7 in arcgis 10.1

I am trying to write a "smart" way in Python to process multiple buffer to lines, polygons and points with different distances. I use Python and ArcMap 10.1. I can figure out to separate lines, ...
2
votes
1answer
158 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 ...
5
votes
4answers
2k views

How to improve 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
1answer
442 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 ...
2
votes
1answer
201 views

How to Buffer based on SQL expression?

Is there any way to optimize this code? It creates two buffer feature classes based on two different fields in the shapefile attribute table import arcpy from arcpy import env ## Set Workspace ...
0
votes
1answer
295 views

Geodjango: Using Lat / Lon to Buffer from Point

I want to have a radius based distance search. To do this, I want to create a buffer around a point object so that I can filter objects that are inside this buffer, a method that I learned based on a ...
1
vote
2answers
68 views

QGIS radius buffer question, can it be more circular?

Conundrum for the day, When I request a radius buffer in QGIS (Dufor). my buffer comes out as a 20-sided polygon rather than a true "circle". This has lead to some missed blocks when clipping ...
1
vote
1answer
46 views

How to extract information from a buffer in ArcMap

I have a buffer in ArcMap 10 extending from a polyline, with numerous 5 km intervals (multiple buffer tool). I also have many layers already in raster format in ArcMap, including slope angle, geology, ...
0
votes
1answer
50 views

USGS Earthquake GPS Metadata: Buffer Zones & Python

I'm making a python web crawler that gets USGS earthquake GPS data, and I'm wondering how I should process the latitude longitude pairs to see if it falls within a specified radius of a specified GPS ...
1
vote
0answers
64 views

How to clip polygons within buffer using QGIS?

I am trying to do the clip operation with polygons in the buffer, so far I'm getting no results. It is working for points in the buffer. Am I doing anything wrong? Basicly I'd like to include ...
0
votes
1answer
49 views

Summing the number of intersections with a separate buffer layer

I have dabbled with ArcGIS and QGIS a bit, and I consider myself a self-taught beginner with a whole lot to learn. So, I have two layers: 1) census blocks, and 2) point data. My goal is to calculate ...
2
votes
2answers
81 views

What's the use of the buffer function in field calculator?

I'm trying to find out how the buffer command in the filed calculator works. I tried to create a new field to my point shapefile (integer) with the following: buffer ($geometry, 100) but no ...
4
votes
3answers
137 views

How to shrink polygon on two sides?

I have a polygon which I know is a rectangle, although it may be at any orientation: I want to shrink this polygon by a third of the width from two sides, so that I just get the strip in the middle ...
2
votes
1answer
164 views

How to create multiple buffers around line at equal intervals without typing in every value?

I have a line in ArcMap 10.2, and want to create lines to the right of it at 100 m, 200 m, 300 m etc. up until 1.7 km. Obviously typing in these values under 'multiple ring buffers' will take too much ...
1
vote
2answers
43 views

Creating Many Uneven Buffers

Qgis 2.2, Windows 7 I am looking to create buffers around city lights (the raster). Currently, I have simple polygon buffers around the point layer (oecdminusa), but this is not accurately capturing ...
7
votes
1answer
141 views

How can I conduct Geographically Weighted Analysis using an exponential decay function?

I have some points (representing 30 study sites) and I want to calculate the weighted mean of several variables (landscape layers) using a negative exponential decay (weights function) to give more ...
0
votes
0answers
56 views

Efficient manner to buffer streams with multiple attributes?

I need to buffer a very large, complex hydro vector layer based on different water quality designations and surrounding slope. Different water quality classifications have different buffer ...
3
votes
1answer
285 views

How to create multi-ring buffers automatically in QGIS?

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 ...
2
votes
0answers
115 views

How to use buffer() in QGIS Value Relation field

When adding a point, I'd like to auto-populate one of its fields (the street address) setting it to a field in the nearest point in another layer (a layer containing all existing addresses). It ...
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 ...
2
votes
0answers
65 views

Zonal Statistics Freezing QGIS 2.2

Running on Windows; 8gb memory, 500gb HD, i5 cpu; Raster file: 250mb I am having a problem with zonal statistics advancing past 17%. I am trying to run statistics on a crop grown in certain counties. ...
2
votes
1answer
103 views

Problem with matching a buffer in Openlayers and the same buffer in PostGIS query

I am using a buffer tool to create a buffer on my base map in Openlayers. In addition to creating and visualizing this buffer, I pass the center point and radius to a query. The query collects all ...
0
votes
1answer
63 views

Remove buffers of overlapping buffers

I work with ArcMap 10.2 and would like to remove buffers of the overlapping buffers, but not all overlapping buffers. So for example: I would like to remove the buffer in the middle and remain the ...