hypersphere_surface, a MATLAB code which investigates a procedure for estimating the location of points on a hypersurface implicitly defined by a characteristic function or by a signed function.
In M dimensions, a characteristic function F for a region of points S has the property that F(X) is 1 for points inside S, and 0 otherwise. A characteristic function is thus discontinous. The set of discontinuity points for F is the boundary of S.
In M dimensions, suppose that the function F, presumably continuous, takes on both positive and negative values. Then we may be interested in the set of points X such that F(X) = 0, which we regard as the boundary between the sets where F is negative or positive. Assuming that F is continuous, or better yet, differentiable, then this boundary may be substantially easier to locate than in the characteristic function case.
The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.
hypersphere_surface is available in a MATLAB version.
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