Barycentric coordinates: Difference between revisions

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imported>Richard Pinch
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imported>Richard Pinch
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In [[geometry]], '''barycentric coordinates''' form a homogeneous coordinate system based on a reference [[simplex]].  The location of a point with respect to this system is given by the masses which would need to be placed at the reference points in order to have the given point as [[barycentre]].
In [[geometry]], '''barycentric coordinates''' form a homogeneous coordinate system based on a reference [[simplex]].  The location of a point with respect to this system is given by the masses which would need to be placed at the reference points in order to have the given point as [[barycentre]].
In an [[affine space]] or [[vector space]] of [[dimension (vector space)|dimension]] ''n'' we take ''n''+1 points <math>s_0, s_1, \ldots, s_n</math> in general position (no ''k''+1 of them lie in an affine subspace of dimension less than ''k'') as a simplex of reference.  The barycentric coordinates of a point ''x'' are an (''n''+1)-tuple <math>x_0, x_1, \ldots, x_n</math> such that
:<math>(x_0+\cdots+x_n) x = x_0 s_0 + \cdots + x_n s_n .\,</math>
The coordinates are not affected by scaling, and it may be convenient to take <math>x_0+\cdots+x_n = 1</math>.

Revision as of 15:44, 1 December 2008

In geometry, barycentric coordinates form a homogeneous coordinate system based on a reference simplex. The location of a point with respect to this system is given by the masses which would need to be placed at the reference points in order to have the given point as barycentre.

In an affine space or vector space of dimension n we take n+1 points in general position (no k+1 of them lie in an affine subspace of dimension less than k) as a simplex of reference. The barycentric coordinates of a point x are an (n+1)-tuple such that

The coordinates are not affected by scaling, and it may be convenient to take .