Balancing the Lifting Values to Improve
the Numerical Stability of
Polyhedral Homotopy Continuation Methods

Tangan Gao, T. Y. Li, Jan Verschelde, and Mengnien Wu

Department of Mathematics
Michigan State University
East Lansing, MI 48824-1027

Abstract:

Polyhedral homotopy continuation methods exploit the sparsity of polynomial systems so that the number of solution curves to reach all isolated solutions is optimal for generic systems. The numerical stability of tracing solution curves of polyhedral homotopies is mainly determined by the height of the powers of the continuation parameter. To reduce this height we propose a procedure that operates as an intermediate stage between the mixed-volume computation and the tracing of solution curves. This procedure computes new lifting values of the support of a polynomial system. These values preserve the structure of the mixed-cell configuration obtained from the mixed-volume computation and produce better-balanced powers of the continuation parameter in the polyhedral homotopies.

Appl. Math. Comput. 114: 233-247, 2000.