Questions tagged [buffer]

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

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125 views

Single Sided Buffer Error QGIS

I have delineated a shoreline and created an offset "buffer" of 75' and 250'. When projected onto the screen it appears as though a computation error has occurred and the buffers extend onto the left ...
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275 views

Using transform function in QGIS layer geometry generator?

I'm trying to use the following expression in the geometry generator in a QGIS layer to show a 1-mi boundary around points: buffer(transform($geometry, 'EPSG:4326', 'EPSG:2877'), 5280) However, the ...
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27 views

How to add raster value with specific equation?

I am trying to develop a raster layer with the interference of streetlight in this example: As you can see there are multiple buffer rings around a point layer. I actually want to transform this ...
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58 views

How to use the output of one run as input to the next in QGIS batch processing?

I'm trying to do a series of buffers using the processing batch interface, and I want to use the output of the first run as the input to the second (and so on). But I can only pick an existing file or ...
4
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74 views

Creating Raster that sums up input polygons using QGIS?

I am using QGIS and I have a shapefile with buildings. From these buildings, I have built Buffer with variegating radius. The Buffer also have data about the demand for Parking spots for each building....
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124 views

Expanding polygons and clipping at midpoint?

I have several separate shapefiles with polygon features. The end goal is to maintain separate shapefiles for each polygon but form a contiguous, non-overlapping coverage for my area. Basically, I ...
4
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0answers
184 views

Drawing “proportional” buffer using QGIS or GRASS?

I'm working on aquatic vegetation and have a shapefile representing floating vegetation in a lake. By some studies, we know that submerged vegetation extends for a certain extension based on floating ...
4
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370 views

How to Simulate Venn Diagram of Buffers using QGIS?

For the sake of simplicity, suppose I have only 2 points on one layer. Point A have population of 100, and point B have population of 150. I do find buffer of these 2 points and it is intersect. I ...
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1k views

Buffering a Raster with GDAL and Numpy

I am using GDAL to convert a raster dataset into a numpy.array and then using numpy to buffer the data in the raster. For example, I need to know all the regions within 100ft of a school point ...
3
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0answers
23 views

Turn disjoint polygons into tessellation

I have a set of points that have labels. These labels represent geographies; however, some of the labels are wrong. Like in the picture below So after running some analysis, I end up with a set of ...
3
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2answers
316 views

Combining ST Buffer and Intersect with Where clause

I'm trying to create a buffer around a single point in a spatial entity and finding all the points from a different entity that fall within that buffer. I tried two approaches. The code below runs ...
3
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0answers
46 views

What is the name of the popular buffer algorithm?

There is a well-known algorithm that I believe is used for the "buffer" function in some GIS libraries and applications. I have a vivid memory of reading the paper that describes the algorithm and ...
3
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0answers
367 views

How to apply a rectangular buffer on spatial polygons in R/qGIS

I am trying to find a way to apply a rectangular buffer on my spatial polygon dataframe in R. At the end, I would like to be able to shrink my polygons by specified units on both sides. So far, I have ...
3
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0answers
79 views

How do I report area statistics for land cover classes at equal sections along a river?

I have a river outlined: Using QGIS, the Semi-automatic Classification plugin and Landsat 8 images I classified the habitats (blue=water, yellow=sand/rock...,green=vegetation/algae) inside the river ...
3
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0answers
281 views

Displaying symbology outside map canvas window extent?

Say we have equally distributed x,y mesh vector file. Each coordinate has a map-unit based diameter circle symbology. If we zoom into a region of the map canvas far enough, some centroids exist ...
3
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354 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 ...
3
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0answers
378 views

Large buffers in PostGIS (5000 km radius)

I have a number of points stored as geographies in PostGIS (version 2.0.1), and I'd like to create rather large buffers around them (with a radius of 5000+ km). However, ST_Buffer doesn't handle this ...
3
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0answers
600 views

Creating a Geodesic Polyline Buffer in OpenLayers

I have a feeling that the answer is going to be 'You can't do that without some very complex coding' but I thought I'd go for it anyway. I recently asked Creating Polyline Buffer in OpenLayers 2?, ...
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42 views

Distance buffer from point, with obstacles

In QGIS is there a tool or technique that would draw a fixed distance buffer from a point, taking into account obstacles in the buffer field? I want to illustrate the maximum distance a ship can ...
2
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0answers
31 views

Selecting a line segment with an azimuth value closest to the azimuth value of another line segment in QGIS

I have a road network dataset and a dataset that consists of multiple disconnected lines of varying lengths in QGIS. Most of these lines are (largely) parallel to the road network, but their shape ...
2
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1answer
91 views

Calculate area with a buffer

I am looking for help for my master thesis. I have two layers, a set of households and burned area (vector data). I created buffer zones around each household and now want to estimate the burned area ...
2
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0answers
44 views

Strange buffer shape when using planar buffer method

I'm doing a very simple operation involving clipping some streams from the National Hydrography Dataset in ArcGIS Desktop 10.3.1, reprojecting them from "GCS North American 1983" into "USA Contiguous ...
2
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0answers
38 views

Variable buffer maximizing mean raster

I was wondering if it exists a way to create variable buffers where the radius is given by a process of maximization of the mean value of a raster. I have a point vector data and I would like to ...
2
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0answers
65 views

QGIS degrees - meters

I have point data in GDA2020. shapefile *.prj file says units are meters. when I load the data in QGIS the layer units are degrees nd the buffer tool is always degrees. I have searched for every ...
2
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0answers
74 views

Calculating variable buffers using slope between river and point 100' away using ArcGIS Pro?

I have a network of streams that I need to buffer based on a basic rule set. This buffer will depend on the slope. The slope is determined by the looking at the difference in elevation between a ...
2
votes
1answer
129 views

Subdividing square buffer in sub-units using QGIS?

I've been trying for a while now to create a grid inside a square buffer, so that it can be divided into a pre-defined number of sub-units. Creating a grid that covers the whole area is not ideal ...
2
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0answers
45 views

Searching on the fly within buffer in QGIS

I am using "Unique Values" widget with "Editable" option in QGIS 2.18.3, for my "Name" field in POIs layer to eliminate spellings mistake. "Unique Values" widget fetches all the distinct values in a ...
2
votes
1answer
318 views

RasterizeLayer in GDAL Java

As per the suggestions given by Michael to one of my earlier query (URL given below), I have tried to develop a sample code to perform rasterize using GDAL Java API methods. I had written based on ...
2
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0answers
201 views

Converting single point layer to buffered raster using QGIS?

I'm trying to use the proximity tool to create a distance raster from a single vector point. I found here: Calculating distance to points in QGIS and [d-3] Create Proximity Raster. However, I couldn't ...
2
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0answers
174 views

QGIS - Label Rectangle/Buffer Overlapping Layer Above

When I apply a buffer or rectangle to my labels they show through the overlying layers. Is there any way to avoid this, i.e. arrange the label so it lies underneath the layers above? I'm assuming the ...
2
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0answers
79 views

“two ways” Reclass QGIS

I'm a forestry technician and I've one question dealing with forest road planning... in order to calculate areas that can be cover by a specific machine (with a given work distance) I do as follow: "...
2
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0answers
197 views

Is there an open source library that offers geodesic buffering of large polygons?

I need to buffer some large polygons and minimize distortion. Is there an open source library that offers negative and positive geodesic buffering of large polygons? I am aware ESRI has an ...
2
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0answers
64 views

wkid error using buffer GeometryService - ArcGIS JS API 3.2

First of all, going to this url for the geometry service referenced in the documentation shows it's been deactivated so I instead chose this url - both with /GeometryServer and /GeometryServer/buffer. ...
2
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0answers
261 views

Flat-ended buffers on touching polygon features in QGIS?

Please note that emphasis is on POLYGON here NOT POLYLINES! I need Buffer/s on one polygon, with two touching features and straight touching parts after difference has been applied I do not want ...
2
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0answers
69 views

Buffer function crashing QGIS only on specific data set

I'm trying to run the buffer tool on a line and it keeps crashing Qgis. The line is created by merging two sets of gps point data and running points to lines with gps_date as the order. I have no ...
2
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0answers
433 views

Fixed Distance Buffer not Buffering Features with Holes

QGIS 2.18.5 I've created a viewshed over a hilly area and I would like to add a fixed distance buffer just to compensate for any underestimations from the viewshed plugin's result. This is the ...
2
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0answers
533 views

GRASS v.buffer.column and v.buffer.distance - Incomplete Output

I have tried .column and .distance buffers within QGIS and both are leaving me with incomplete results. Only a few of the features within my input file are actually being buffered. I also have both "...
2
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0answers
94 views

Automatically split line at intersection of nearby shapes/zones

I have a large dataset in QGIS with roads (blue line in picture below) and 3 type of zones (mostly rectangular areas, red and green shape in picture below). My task is to spilt to road into segments ...
2
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0answers
71 views

Creating a cumulative factor based on multiple buffers

I'm using QGIS 2.12.0 and am trying to formulate a hierarchy for the risk factor associated with footpath polygons based on their proximity to pedestrian generators and the importance factor of that ...
2
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0answers
2k views

Extract values from Rasters in R based on spatial points and spatial polygons

I am trying to extract values from a raster file using the extract command in R mentioned here: http://www.inside-r.org/packages/cran/raster/docs/extract My raster file is unprojected (WGS84 ...
2
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0answers
199 views

How to create buffers having regard to topography with QGIS

I want to create buffers of 25 kilometers around points in a point-shapefile with QGIS. My problem is that I don't need an air-line distance of 25 km around the points, but a "real distance" having ...
2
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0answers
260 views

ST_Buffer with segment AND endcap parameters

Making a QGis plugin that buffers a line and I want to declare a high number of segments and a flat endcap. ST_Buffer(geom, 40, 25, 'endcap=flat') This doesn't work with both parameters entered, it ...
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0answers
73 views

Distribute Hotel Beds According to Population Density in Buffers using ArcGIS for Desktop?

I am running an ArcGIS for Desktop analysis where I am plotting competing hotel facilities and then distributing their beds in a 5-mile buffer around the site. I would like to distribute the beds ...
2
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0answers
76 views

Distribute population to health facilities (GP Practices)

I have been using GIS (ArcGis) for some years but I do not consider myself an expert. I am performing some analysis around GP Practices in London (UK), I would like to be able to estimate the ...
2
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0answers
207 views

How to spatial join points attributes to layer with two (or more) overlapping buffers in QGIS?

I'm working with QGIS 1.8 and I've got 3 layers : 2 points layers, and 1 layer composed of the buffers of one of the points layer. I'd like to retrieve the informations, for the point layer that isn'...
2
votes
1answer
765 views

Variable buffer radius in ArcGIS JavaScript API?

I'm trying to combine the following Esri samples, to end up with the ability to create buffers based on a variable radius, that will then query data within the buffer zone. https://developers.arcgis....
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17 views

How can I identify points that share similar attribute with polygon features based on the attribute & distance between the two?

For Example; if both the point & polygon features have an ID field, I need to flag the points if they share the same ID as a neighboring polygon & are w/in 2000ft of each other. I have tried ...
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0answers
17 views

How to calculate the exact area of three 1 km buffers that have been intersected?

I am trying to figure out the exact area of overlap of the 1 km buffers around three survey posts. I have used the Intersect tool to produce three individual intercepts which cover all the overlap of ...
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0answers
35 views

Buffer around shoreline hitting user memory limits

I am having issues hitting user memory limits creating a buffer around a shoreline. I think its because there are too many elements in the feature collection. This might be a tiling issue? How do I ...
1
vote
0answers
23 views

Calculate area within a buffer zone

I am working on 3.12.0-București. I have created buffers (radius=300 meters) on a set of sampling points. I do not remember the number of segments that I have used. However, I have set a high number ...