A circle is a simple shape of Euclidean geometry that is the set of all points in a plane that are a given distance from a given point, the centre.

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32 views

How do I get imported KML circles to appear as circles rather than ellipses in QGIS?

I have a QGIS project, CRS is WGS84 (EPSG 4326). I have OpenStreetMap as the base layer. I have loaded some point features. I have created a buffer zone around some of these features with WGS84 as ...
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0answers
34 views

How to remove circles from new polygons in QGIS? [closed]

I've just started using QGIS (2.6.0-Brighton). Every time I create a new polygon, a circle appears in the center (see below). I thought this might just be a feature of QGIS editing that helps you to ...
2
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1answer
48 views

How a draw a circle (on the surface of earth) on a mercator projection?

I would like to use R and leaflet to draw a circle (a real circle on the surface of the earth) on a mercator projection. In the following code, I have the center of the circle (with lng=0 and lat=60),...
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1answer
44 views

Point buffer not round - jagged circle like thing

Any ideas why running a point buffer (50 and 150 meters) would result in this shape? ArcGIS 10.2 - All projections match
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1answer
52 views

Google Earth: Circular polygons that follow earth curvature

I'd like to draw filled circles in Google Earth which follow the curvature of the earth, i.e. for 1000ft altitude, not only the circle's edge but also the center is required to be 1000ft above ...
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1answer
145 views

Drawing circle with OpenLayers3, but not seeing on map?

I am trying to draw a circle on a map, using open layers 3, but I am not sure why the circle is not rendering. My expectations with the code below is that is should be centering on -73.5971431341708, ...
2
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1answer
51 views

Circles and Projection in ArcGIS for Desktop?

I am using ArcGIS 10.2 and when I run topology on my feature class (which is in NAD 83 Lambert_Conformal_Conic) there were no overlaps. Once I project it into any projection I get overlapping polygons ...
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2answers
70 views

Leaflet: Capturing points for features inside circle

I'm using the leaflet draw tool to create a circle and then finding the points inside the circle. My data is from GeoJSON, and the code works as far as figuring out how many points are inside, but I ...
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1answer
89 views

How to store circle in GEOJSON for OpenLayers 3

I am loading my layers from external files - I am using geojson format for it, but it's not necessary - I can use any available format. Is there a way, how to store a circle (ol.geom.Circle) in the ...
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2answers
64 views

How to turn a point layer into classified proportional circles in QGIS 2.12?

I'm trying to style a point layer representing cities around the Mediterranean following these two rules : The points should be represented as proportional circles, following a classification in 5 ...
2
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1answer
192 views

GeoDjango, distance filter based on database column

I have a geodjango model with fields coverage = 10 * 1609.344 reference_point = Point(-72,45) #or some other lat lng class ServiceArea (geo_models.Model): center = geo_models.PointField(default=...
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1answer
78 views

Calculate total coverage of circles on map with PostGIS

I am trying to calculate the total area covered by c.a. 400 Circles of diameter 15Km. The centers of these circles are stored in a column of type geometry:4326 in my database. Some circles overlap, ...
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1answer
66 views

How can I create a 3 Hectare circle around a point

Does anyone have any suggestions on how I can create a 3 Hectare circle around a point quickly? I am using arcmap 10.3.
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0answers
16 views

Quantum gis 2.2 - pasting templates

Is there a way to paste geometries in a workspace at the location i want? e.g. i want to paste a circle from another workspace in the workspace i'm working with. I need only the geometry, not the ...
2
votes
1answer
55 views

Moving circle using QGIS?

Using QGIS 2.2, I want to move a circle from one specific point to another specific point: How can i grab the exact center of the circle and move it to another location without creating points in the ...
2
votes
1answer
355 views

Create Circle and Marker on Click in OpenLayers

I want to create a marker and buffer around it with a given radius on map click event. Marker is displayed successfully but the polygon doesn't display. I guess there is problem in projection setting. ...
2
votes
1answer
342 views

Leaflet cirlceMarker changes with zoom

I was under the impression that L.circle changes size with zoom, but L.circleMarker should remain the same radius as you initially set? I've setup an example here, which ever I choose the circle ...
2
votes
1answer
181 views

How to calculate the form (or shape) factor of a polygon?

I am using QGIS to calculate the form (or shape) factor of polygons following what Louf and Barthelemy did here: http://rsif.royalsocietypublishing.org/content/11/101/20140924 The form factor is ...
0
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1answer
56 views

find minimum covering circle for given points (long,lat)

Hi need to be able to calculate a bounding box or circle for Given points (latitude and WGS84 longitude). Would it be possible for someone to give me some pointers / Example on how to do this Thanks.
4
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1answer
350 views

Find Intersection of Two Circle given Lat/Lon and radius

I am attempting to calculate the intersection of two circle on the Earth with a given latitude, longitude and radius. I started with this post. These circle will never be more than 100 km in diameter ...
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2answers
427 views

How to make a circular polygon in QGIS?

I am trying to make a floor plan for my office, have managed to make all of the rectangular components (e.g. the rooms) however some of the desk layouts are circular and I haven't been able to work ...
2
votes
2answers
424 views

Create circle shapefile vector in QGIS

Is it possible to create a circle shapefile feature in QGIS, like it is possible to do in ArcMap? I am trying to digitise a map wich features roundabouts, which I'd like to be part of the same ...
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1answer
72 views

Counting points in concentric circle buffer zones of different sites in a map? [closed]

I produce concentric circles of 200 and 500 m buffer zones to see water points within each buffer zones. The buffer zones are created throughout my study area. How can I count the points found in ...
0
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2answers
418 views

Create a circle polygon in GMaps.Net?

I found this function and converted it to VB.Net. It draws an oval rather than a circle. What do I need to do to fix the calculations? Dim seg As Double = Math.PI * 2 / segments For i As Integer =...
4
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4answers
1k views

Checking if polygon fits inside another polygon using ArcGIS or QGIS?

How do I check if one polygon fits inside another polygon? Furthermore how do I automatically check if one polygon fits in other polygons of my shapefile? I have a shapefile with thousands of ...
2
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0answers
46 views

Help Summing Raster cells to equal circles with a specific sum

So I have this application user density data that I've collected. Each gps point has a user density associated with it (for example: 150 users within a 1 km radius, which calculates to users/[pi*R-sq] ...
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1answer
1k views

Using WKT.writeGeometry for 'Circle' Geometry in OpenLayers?

In my application which I'm building using OpenLayers3, I'm trying to extract the geometry of a feature to WKT using var format = new ol.format.WKT(); console.log(format.writeGeometry(geometry)); by ...
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0answers
173 views

finding circumcenter of circle assuming 3 geo points on circumference (lat/long)

Situation: I have 3 geo points (lat/long). I have to draw a circle on a map where these 3 points are "sitting" on a circle circumference (max-distance from point to point = 500 Meters). So I need to ...
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1answer
75 views

Create Multiple Circle

I am trying to make many points in a map as a grid. The code makes what I expect but the time to load is quite long so I suppose that there should be other ways to be more efficient drawing many ...
2
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1answer
869 views

Openlayers 3 Circle Vectors Not Visible

I have two coordinates which are projected in EPSG: 3857 coord1 = [-10399758.486973494, 5604341.818491254] coord2 = [-10402629.416641055, 5593700.936383396] I'm trying to get them to appear, ...
1
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1answer
86 views

How to display radius while adding element in ArcObject?

I want to display the radius of drawing circle when user adds this figure on the map. User clicks on the icon. Then user begins drawing circle (I process the MouseDown event) IGeometry geom = Map....
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0answers
136 views

Solution to draw objects on layers and share maps

I'm looking for an online solution to build custom maps on top of OSM/Bing/Google layers and share them via export or link. I need to find an address, draw and drop lines, polygons, circles, add and ...
2
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1answer
1k views

Leafletjs get latlng center position of polyline

After drawing a polyline, I would like to draw a circle from the center of this line whose radius encompasses the entire line. For polyline's that have more than 2 points I can crudely get the center ...
0
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1answer
226 views

limiting circles to a specific radius

I am new to ArcGIS javascript api and I have created a map which allows users to draw circle geometries. I just want to limit the functionality so that the radius is specified at 10000km. This is ...
4
votes
2answers
5k views

How to create circular polygon in openlayers 3?

So i would really like to modify this example: http://openlayers.org/en/v3.0.0/examples/tissot.html?q=circle Problem there is that wheter i try to apply it to my map it doesen`t work, probably ...
1
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1answer
79 views

How to create circle that contains a certain number of points?

In ArcGIS 10.2 (with spatial analyst ext). I have two point layers. One represents schools and one represents students. For each school I have a number of students living near the school I need to "...
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0answers
141 views

How can I find the center of the circle or ellipse I just created

I need to draw circles and ellipses with a certain length/width/ radius. I used the rectangles ovals digitizing plugin to create them, but only measured roughly the circles' radiuses. It would be ...
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votes
2answers
943 views

How to draw a perfect circle with a set radius in meters on map?

Following this istructions on how to draw a circle I can make buffer layer on each point I need. I am not able to draw perfects circle because the buffer will be elliptic? The CSR is EPSG:4326 - WGS ...
3
votes
1answer
192 views

Extract longitude latitude and radius from POSTGIS column

I have entered the circle in the Geometry type column (name=shape) in my POSTGIS as following: ST_Buffer(ST_MakePoint($longitude, $latitude)::geography, $radius)::geometry Then I extracted the ...
2
votes
2answers
1k views

drawing concentric circles in arcmap 10.1

I am using ArcMap 10.1 and I would like to know if there is a way to draw circles at a specific distance from a georeferenced coordinate. I have a property and I would like to know how far you can ...
2
votes
0answers
169 views

Air corridor in spherical surface: calculating great circle tangent points with small circles

I have the necessity to draw on a sphere (earth) an air corridor. In the cartesian plane, this corridor is made by some circles and from outer tangents that connect these circles as you can see in ...
0
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1answer
345 views

How can I get the circle of a sphere (on Earth ellipsoid) around a point using the Latitude and Longitude?

Specifically finding points along the circle. If possible without converting into Northing/Easting beforehand. I'm looking for the fastest possible way to calculate points in Latitude/Longitude in a ...
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0answers
126 views

Determine the list of circles (from 100K circles), that overlap with a given polygon

This question was asked on StackOverflow, came here because no response has been posted so far. Existing data structure we have polygons represented as an ordered list of lat/long coordinates and ...
1
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0answers
250 views

How to create a circle vector layer with 12 sectors with Python and to save average value of underlying raster in each sector?

Hi I am writing a code with Python 2.7 using Arcpy 10.1 and I guess I am doing stuck with a silly problem that lies under my eyes. I have created a grid of points (with "Create fishnet" function) over ...
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1answer
592 views

Python: Ray-trace a WGS84 point with heading and distance

One of my services defines geofences for a mobile app. The geofences consists of a lat/lon pair and radius in meters, in JSON, e.g.: { "geofenceId":"geofence_b39da38cff7be4b4693cbc31b2394bbb", ...
0
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0answers
28 views

Quickest method for determining which postcode is 2 miles north of original postcode? [duplicate]

What is the Quickest method for determining which postcode is 2 miles north of original postcode? For instant L17. I know how to determine the distance between 2 points as below, but the above ...
0
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1answer
47 views

Hard to get my head around, generating average price for houses in each quadrant

I'm able to determine the average price of houses sold in a particular area (like the squares on image below) dependent upon postcode. Although I can generate the average sale price for a particular ...
1
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2answers
990 views

Is there an average size for British postcodes?

Is there an average size for British postcodes? Or a method of determining the size for a particular British postcode? Thanks. Considering creating a related program and this would be valuable ...
1
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1answer
163 views

How do I convert OS coordinates (X and Y) to longitude and latitude coordinates?

How do I convert OS coordinates (X and Y) - Eastings and Northings to longitude and latitude coordinates? For example X and Y below X (Eastings): 347904 Y (Northings): 287484
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1answer
265 views

How do I figure out the grid references (Eastings and Northings) necessary to create a circular 1 mile radius around one location?

How do I figure out the grid references necessary to create a circular 1 mile radius around one location? For instance: Grid Reference: SO 47904 87484 X (Eastings): 347904 Y (Northings): 287484 ...