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arXiv · 1909.03112

Knot Locating in Piecewise Linear Approximation

Carlos Ugaz·Lanshan Han·Alvin Lim
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Abstract

Many separable nonlinear optimization problems can be approximated by their nonlinear objective functions with piecewise linear functions. A natural question arising from applying this approach is how to break the interval of interest into subintervals (pieces) to achieve a good approximation. We present formulations to optimize the location of the knots. We apply a sequential quadratic programming method and a spectral projected gradient method to solve the problem. We report numerical experiments to show the effectiveness of the proposed approaches.

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Carlos Ugaz, Lanshan Han, Alvin Lim. 2019-09-06. Knot Locating in Piecewise Linear Approximation. https://arxiv.org/abs/1909.03112

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