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

learn more… | top users | synonyms

1
vote
2answers
138 views

Buffer View With SpatiaLite and QGIS

Creating a dynamic buffer with PostGIS the following view is working: CREATE VIEW buffer500m AS SELECT gid, st_buffer(geom,500)::geometry(polygon,31492) AS geom FROM point; Unfortunately this query ...
2
votes
1answer
553 views

Create random points in ArcGIS on a polyline in a polygon

I am trying to create 100 random points, 1 within 500m of 100 points I already have. I have created a buffer and can easily create 1 random point in each, but now I want those points to lie on a ...
5
votes
1answer
375 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?
1
vote
1answer
96 views

Buffering line in ArcMap is creating smaller buffer than expected?

When I buffer a point (red dot on image) by 3 miles, it is 3 miles on all sides. When I buffer a line (blue line on image) by 3 miles, it is more like 2.67 miles on the sides parallel to the line. I ...
1
vote
1answer
455 views

How to create dissolved buffers in QGIS with PostgreSQL/PostGIS?

Creating a dynamic buffer in QGIS I use the following query: CREATE VIEW buffer40units AS SELECT gid, st_buffer(geom,40)::geometry(polygon, 31492) AS geom FROM point; Now I want to dissolve ...
2
votes
0answers
89 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, ...
1
vote
0answers
108 views

Catchment area calculation

I have a conundrum. I am trying to shortlist optimal physical locations in my county for developing recycling centres that serve the population. I have a vector point layer of the centre point of ...
2
votes
2answers
119 views

Create buffer along shoreline near sample site

I want to look at the land use on the shoreline of a river relative to a specifc point on the river. I have created a point on the shoreline using the Near tool. Following this I am having trouble. I ...
0
votes
1answer
137 views

PyQGIS point buffer with OpenLayers base map

Using PyQGIS, I desperately need help on creating a buffer around a point in a node layer and then selecting features from a trails layer that fall within the buffer. When I load the shape files ...
2
votes
1answer
47 views

Point buffer problem

I have a point feature that I would like to buffer to select segments that are within 15 meters of the point. The code I have is working but it's influenced by the map scale. Zooming in or out changes ...
2
votes
0answers
72 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 ...
2
votes
2answers
2k views

How to perform a buffer analysis in PostGIS?

Need to Implement Spatial Analysis in Postgresql. Can Any one guide me to accomplish the spatial analysis eg) 2 km buffer for road network layer.
0
votes
1answer
304 views

Intersecting Overlapping Polygons Individually in ArcGIS

Map Layers: -Census Tract Shape File w/Population Data -Set of Store Locations with 5 Mile Buffers (Significant Overlap Between Buffers) I have create feature layers for both and I am trying to ...
4
votes
1answer
121 views

Buffering Points Directionally

I have about 10,000 points that I want to apply a partial circular buffer to based on an angle, from -30 to 135°. A similar question for polygons seems to have been answered here, but I cannot make ...
5
votes
3answers
2k views

Create buffer around point in LeafletJS?

I am using LeafletJS. I want to create buffer around point. after Selecting a point buffer radius will be specifed by user in feet. After searching of awhile I found this link of JSTS. does JSTS ...
0
votes
1answer
163 views

Use turf.count with turf.buffer dynamically

I have this code where I'm trying to create a buffer dynamically from a draggable marker and then count how many points fall insed this buffer. As of now I can drag the buffer around without any ...
0
votes
1answer
66 views

How to set a label's buffer color in a mapfile?

I would like to set a white buffer around labels in a mapfile (Mapserver version 6.2.1). In the official documentation, I can't find a specific parameter for this... I have tried the SHADOWCOLOR and ...
0
votes
0answers
73 views

For every point create a wedge

How does one create a wedge polygon from a point? If I have 2000 points, I want each to have a wedge starting at each point with each point having a defined azimuth that the wedge points toward. That ...
2
votes
1answer
91 views

Multiple Ring Buffer in ArcPy Generates Single Ring

I'm running a simple multiple ring buffer using ArcPy. My goal is to generate a multi ring buffer for each pond in my dataset of 50,000. Here's the line of code: ...
3
votes
1answer
68 views

Extending buffer zone

I am working in ArcMap 10.2 (and Modelbuilder) and I would like to solve the following problem: I have Buffer A (single part) and Buffer B (multipart). I would like to extend Buffer A with Buffer B ...
1
vote
1answer
101 views

Iterating through a point layer to create & sum distance rasters

I'm writing an Arcpy program to process data in a layer of several hundred points ('ptsLyr', from file 'ptsFile'), each of which has its own ID ('RecordID') and an associated value, 'radius', that I ...
3
votes
1answer
140 views

Python code for decreasing polygon size based on percentage?

I would like to decrease the size of polygons by percentage and not by distance in order to implement this into ModelBuilder to loop over a number of polygons. To my knowledge this tool is available ...
2
votes
2answers
54 views

Assigning values of points outside a buffer to points within a buffer

I have 10m buffers around line features and a point shapefile which has some points intersecting the buffer. I would like to take each point that falls within the buffer and assign it the value of the ...
1
vote
1answer
129 views

Euclidean distance outside a Polygon (ArcMap)

I got some university coursework to analyse the best potential areas for a residential development project and I'm currently doing multi-criteria evaluation. One of the shapefiles in the dataset given ...
1
vote
1answer
159 views

Multi-Ring Buffer Methodology

When creating a multi-ring buffer I see two methodologies: Create buffer around feature, buffer the resulting buffer, and repeat for as many rings as required. Using the initial feature to create ...
1
vote
2answers
126 views

Counting buffer overlap in QGIS

For my thesis I'm modeling the identification of recreation areas. Therefore, there has been a survey where people were asked to specify where they recreate. They had to indicate this place on a map ...
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. ...
0
votes
0answers
84 views

Proper size of buffer to represent village boundary using Geonames populated places

I am trying to estimate population for each Geonames populated place (PPL) in Tanzania. There are about 8000 PPL, represented by point features, however population data is missing. I used ArcGIS to ...
0
votes
1answer
149 views

QGIS: How to add a second polygon that is exactly 5km larger in all directions?

Given is a map with an airport. Within a distance of 5km around the runway there is a so called no fly zone for drones (in Switzerland). I want to show this zone in a map. What I would like to do is ...
1
vote
1answer
162 views

QGIS 2.6 Buffering issue

I'm running QGIS 2.6 on a Mac, and trying to create buffers around a point shapefile. The process seems to work: (Vector>Geoprocessing Tools> Buffer(s), I select my input layer, leave the segments at ...
25
votes
6answers
1k views

How to buffer raster pixels by their values?

The pixels to the left represent tree locations and their associated crown radii (i.e. pixel values ranging from 2 - 5). I would like to buffer these raster pixels by their crown radius value. The ...
1
vote
1answer
231 views

Trouble buffering a vector layer in QGIS with PyQGIS

I am working on a script that imports a .csv layer that has lat long coordinates, which I then want to buffer in feet. I've created a vector layer from the .csv file and tried to set the coordinate ...
1
vote
2answers
618 views

Calculate area size within a buffer

I have a park polygons layer and a set of points which I gave a 1000m buffer. For each of them I had calculated the area size with calculate geometry. So with which tool could I calculate the size of ...
2
votes
1answer
2k views

calculate the population inside a buffer with census data

I have population data matched with polygons and a set of points that I have drawn buffers around. Assuming that the population within each geographical area, i.e. the polygons, is evenly distributed, ...
1
vote
0answers
86 views

Problem with ST_SummaryStats, ST_Buffer, and casting between geometry/geography types

I have a test raster that covers the world ((-180 90), (180 -90)). The SRID is WGS 84 (EPSG:4326). Values for cells in the north-western quadrant ((-180 90), (0 0)) are random integers in the range 1 ...
1
vote
1answer
142 views

How to do a buffer operation for a polygon drawn by the user using python in QGIS

I have a polygon drawn on the map canvas.Say the polygon would be drawn by using "Measure Area" tool in qgis.Now, I want to do buffer for certain distance around that polygon.I can see the below ...
5
votes
3answers
416 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 ...
0
votes
0answers
45 views

Multibuffer in arcpy is too slow?

I have to make multibuffer to a several shp's (30 or +) and with this code the it takes 30 minutes or more. import arcpy,time,glob,os def multibuffer (probe,Zona_trab,nombarch3,recortes2): ...
3
votes
2answers
1k views

Buffer Polygon, BUT Inside and Only for a Distance

There has to be an easy way to do this. Been plugging away for an hour and I don't know if I am brain dead or what. What I need to do is buffer a polygon on the inside, but only for 500 metres. If ...
2
votes
1answer
39 views

On-The-Fly ModelBuilding

I am wondering to change and alter a model on the fly. I have a whole process( model for the rest is done) that relies on different settings for buffers, and what I am trying to do is after I am not ...
4
votes
0answers
436 views

How to create multi-ring buffers automatically in QGIS? [duplicate]

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 ...
1
vote
1answer
207 views

Are there reference manual pages anywhere for QGIS built-in “buffer” and plugin “points2one”?

Perhaps I am missing some quick pop-up help mechanism, but as a relative newcomer to QGIS (having cut my teeth on ArcGIS 10.1), I am struggling to find reference manuals (i.e. explanations of all ...
5
votes
1answer
736 views

Calculate population within radius

I have population data matched with polygons and a set of points that I have drawn buffers around. Assuming that the population within each geographical area, i.e. the polygons, is evenly distributed, ...
0
votes
2answers
75 views

FID attribute for each circular buffer polygon

I have a point shapefile "Negative_vel". With the command Analysis tools-Proximity-Buffer and selecting 50m as a linear unit and dissolve type ALL I created a new .shp "Negative_vel_buffer50m". But ...
1
vote
1answer
87 views

Buffering in km in NAD83 QGIS

I need to create a 32.1869 km (20 miles) buffer around my attributes, but the problem is the CRS needs to stay in NAD83. Is there a work around so I will be able to create buffers in km but still have ...
2
votes
0answers
161 views

QGIS buffer polygon with different widths on each side

I create maps for wildfire risk assessments and am constantly asked to plot "defendable space" buffer zones around building envelopes that are different distances on different sides of the buildings. ...
1
vote
1answer
152 views

Use ST_Buffer with a conditional distance based on an attribute

I am quite new to postgres/postgis and are still learning basic skills. I have imported a pointlayer shapefile into my postgres database. I need to make a buffer of varying radius around the points ...
0
votes
2answers
1k views

Calculate sum of points within buffer (ArcMap)

I've created buffers around home origins and am looking to calculate the sum of shapefiles (in this case crime) within each buffer. How would I go about doing this? I want to know how many crimes are ...
1
vote
0answers
239 views

Multiple ring buffer (and query) in arcgis Silverlight

How could I build a multiple ring buffer/query analysis in my silverlight project? I have a working evacuation zone analysis in my project where I can query all elements within a specified distance ...
0
votes
1answer
127 views

How does ArcMap buffer linear features?

Two methods of selection in ArcMap that I thought would be the same are in fact not equal. I created a 3 mile buffer around a single line feature (approx 6mi in length). I'm working with parcels, as ...