In mathematics, an ellipse is a plane curve that results from the intersection of a cone by a plane in a way that produces a closed curve. Circles are special cases of ellipses, obtained when the cutting plane is orthogonal to the cone's axis. An ellipse is also the locus of all points of the plane ...

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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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Creating ellipse with azimuth according to projected North not to geodetic North with ArcGIS Tool Table to Ellipse?

Table to Ellipse allows the user to create ellipses according to self-defined parameters. One of those parameters is azimuth. As written in the tool help the azimuth refers to the angle 0°-360° ...
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Create Two Ellipse/Arcs from Straight Line Segments

I have thousands of straight line segments (all separate features). I need to convert each straight line segment into two arcs, with the arcs opposite of each other. For example, I used the XY to Line ...
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Using JTS to rotate a Polygon doesn't seem to be working

I am using JTS to create a Polygon - the Polygon creates properly (with the right dimensions and in the right place), but rotation seems to stretch the shape and not rotate properly. I have a video ...
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Table to ellipse not working properly

I have a point shapefile with fields major_axis, minor_axis, azimuth, POINT_X and POINT_Y. There are values in those fields. I run Table To Ellipse, it goes without errors but what i get at the end is ...
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How do I use EllipseMarker in QGIS 1.8?

I've tried setting the Symbol width, Symbol height and Rotation of an EllipseMarker to be data defined in QGIS 1.8, but I can't seem to get it to work. What units does it expect those values to be in? ...
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Concentric Ellipses around polygons as a representation of density

I have someone who has given me a thumbnail of a map with some concentric ellipsoids placed in estimated high density locations for our business. One location has three, and two other location have ...
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Postgis - Creating Ellipse in WGS84 with metric parameters

I have points in WGS84 (x,y), radiuses in meters (rx, ry), rotation angle in degrees. I would like to create a new WGS84 geometry. I've tried this but the major/minor distances seem to be off by a ...
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Generate a series of ellipses on a line

I am trying to create a series of ellipses (mocked up in green below) of defined dimensions along a line. I have got as far as generating regularly spaced points along the line that are attributed ...
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Is it possible to create an ellipse around a line in 3D space?

In Postgis 2.1.1, I have a line in 3 dimensional space connecting two antenna points on the earth's surface. Is it possible to create an ellipse around that line? I have a formula to compute the ...
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Creating Irregular ellipses using SQL Spatial 2012 Geometry

I have stumbled across a problem in SQL Server 2012 - whereby I need to create different shape ellipses from the following data points: centre_x | centre_y | max_x | max_y | min_x | min_y I have ...
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Can ArcPy 10.1 be used to generate true curve elliptical polygons in a file geodatabase?

As background, this question arose from trying to answer a question on How to generate overlapping polygons from lines output from Table To Ellipse tool? Using the ArcMap GUI it is very easy to ...
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Drawing Ellipse with OpenLayers

I am trying to draw ellipse on the client side using openlayers with some mathematical functions from drawing ellipse with svg. I have achieved drawing it but not rotation what I have written for ...