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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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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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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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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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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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? ...