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@@ -107,10 +107,10 @@ a flat surface is a straight line, the shortest path between two points on a cur
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surface (such as the earth) is an *arc* of a `great circle`__. [#fnthematic]_ Thus,
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additional computation is required to obtain distances in planar units (e.g.,
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kilometers and miles). Using a geographic coordinate system may introduce
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-complications for the developer later on. For example, PostGIS versions 1.4
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-and below do not have the capability to perform distance calculations between
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-non-point geometries using geographic coordinate systems, e.g., constructing a
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-query to find all points within 5 miles of a county boundary stored as WGS84.
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+complications for the developer later on. For example, Spatialite does not have
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+the capability to perform distance calculations between geometries using
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+geographic coordinate systems, e.g. constructing a query to find all points
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+within 5 miles of a county boundary stored as WGS84.
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[#fndist]_
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Portions of the earth's surface may projected onto a two-dimensional, or
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@@ -124,10 +124,9 @@ calculations.
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.. note::
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If you wish to perform arbitrary distance queries using non-point
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- geometries in WGS84, consider upgrading to PostGIS 1.5. For
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- better performance, enable the :attr:`GeometryField.geography`
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- keyword so that :ref:`geography database type <geography-type>`
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- is used instead.
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+ geometries in WGS84 in PostGIS and you want decent performance, enable the
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+ :attr:`GeometryField.geography` keyword so that :ref:`geography database
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+ type <geography-type>` is used instead.
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Additional Resources:
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Claude Paroz