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Shape preserving least-squares approximation by polynomial parametric spline curves. (English) Zbl 0893.68156

Summary: This article presents a method for shape preserving least-squares approximation. This method generalizes an algorithm of Dierckx to the case of planar parametric curves. Using a reference curve we generate linear sufficient conditions for the convexity of the approximant. This leads us to a quadratic programming problem which can be solved exactly, e.g., with an active set strategy.

MSC:

68U05 Computer graphics; computational geometry (digital and algorithmic aspects)

Software:

FITPACK
Full Text: DOI

References:

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