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arXiv · 2403.14844

Extrapolating Solution Paths of Polynomial Homotopies towards Singularities with PHCpack and phcpy

Jan Verschelde·Kylash Viswanathan
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Abstract

PHCpack is a software package for polynomial homotopy continuation, which provides a robust path tracker [Telen, Van Barel, Verschelde, SISC 2020]. This tracker computes the radius of convergence of Newton's method, estimates the distance to the nearest path, and then applies Pad\'{e} approximants to predict the next point on the path. A priori step size control is less sensitive to finely tuned tolerances than a posteriori step size control, and is therefore robust. The Python interface phcpy is extended with a new step-by-step tracker and is applied to experiment with extrapolation methods to accurately locate the singular points at the end of solution paths.

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Jan Verschelde, Kylash Viswanathan. 2024-03-21. Extrapolating Solution Paths of Polynomial Homotopies towards Singularities with PHCpack and phcpy. https://arxiv.org/abs/2403.14844

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