Abstract
Univariate polynomial root-finding has been studied for four millennia and still remains the subject of intensive research. Hundreds if not thousands of efficient algorithms for this task have been proposed and analyzed. Two nearly optimal solution algorithms have been devised in 1995 and 2016, based on recursive factorization of a polynomial and subdivision iterations, respectively, but both of them are superseded in practice by Ehrlich’s functional iterations. By combining factorization techniques with Ehrlich’s and subdivision iterations we devise a variety of new root-finders. They match or supersede the known algorithms in terms of their estimated complexity for root-finding on the complex plane, in a disc, and in a line segment and promise to be practically competitive.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Notes
- 1.
Required precision and Boolean time are smaller by a factor of d, the degree of the input polynomial, at the stage of numerical polynomial factorization, which has various important applications to modern computations, besides root-finding, e.g., to time series analysis, Wiener filtering, noise variance estimation, co-variance matrix computation, and the study of multi-channel systems (see Wilson [59], Box and Jenkins [7], Barnett [3], Demeure and Mullis [16] and [17], Van Dooren [56]).
- 2.
- 3.
We count m times a root of multiplicity m.
- 4.
Here and hereafter we write \(\tilde{O}(s)\) for O(s) defined up to a poly-logarithmic factor in s.
- 5.
- 6.
Furthermore we may have ITER\(_f<\)ITER\(_p\) because of the decrease of the maximal distance between a pair of roots and of the number and sizes of root clusters in the transition from p to the polynomial f(x) of a smaller degree w.
- 7.
[50] supplies estimates for the working precision in such a recursive process, which ensure the bound \(1/2^b\) on the errors of the output approximations to the roots of p.
- 8.
The wild roots are much less numerous than the tame roots in a typical partition of a root set observed in Ehrlich’s, Weierstrass’s and other functional iterations that simultaneously approximate all roots of p as well as in Newton’s iteration in [54]. Consequently the coefficient growth and the loss of sparseness are not dramatic in the transition to the factors defined by the wild roots.
- 9.
- 10.
The DLS algorithms (cf. [42, Appendices A and B]) approximates a factor f at a nearly optimal Boolean cost if the disc \(D'_i\) is \(\theta \)-isolated for isolation ratio \(\theta =1+g/\log ^{h}(d)\), a positive constant g and a real constant h. Such an isolation ratio is smaller than those required in [11, 35, 49] and [12] and thus can be ensured by means of performing fewer subdivision steps.
- 11.
Then again with such a delay we bound the overall cost of all deflation steps (cf. Example 1), avoid coefficient growth and do not lose sparseness.
References
Bell, E.T.: The Development of Mathematics. McGraw-Hill, New York (1940)
Boyer, C.A.: A History of Mathematics. Wiley, New York (1968)
Barnett, S.: Polynomial and Linear Control Systems. Marcel Dekker, New York (1983)
Bini, D.A.: Parallel solution of certain Toeplitz linear systems. SIAM J. Comput. 13(2), 268–279 (1984)
Bini, D.A., Fiorentino, G.: Design, Analysis, and Implementation of a Multiprecision Polynomial Rootfinder. Numer. Algorithms 23, 127–173 (2000)
Bini, D.A., Gemignani, L., Pan, V.Y.: Inverse power and Durand/Kerner iteration for univariate polynomial root-finding. Comput. Math. Appl. 47(2/3), 447–459 (2004)
Box, G.E.P., Jenkins, G.M.: Time Series Analysis: Forecasting and Control. Holden-Day, San Francisco (1976)
Bini, D., Pan, V.Y.: Computing matrix eigenvalues and polynomial zeros where the output is real. SIAM J. Comput. 27(4), 1099–1115 (1998). Proc. version. In: SODA 1991, pp. 384–393. ACM Press, NY, and SIAM Publ., Philadelphia (1991)
Bini, D., Pan, V.Y.: Graeffe’s, Chebyshev, and Cardinal’s processes for splitting a polynomial into factors. J. Complex. 12, 492–511 (1996)
Bini, D.A., Robol, L.: Solving secular and polynomial equations: a multiprecision algorithm. J. Comput. Appl. Math. 272, 276–292 (2014)
Becker, R., Sagraloff, M., Sharma, V., Xu, J., Yap, C.: Complexity analysis of root clustering for a complex polynomial. In: International Symposium on Symbolic and Algebraic Computation (ISSAC 2016), pp. 71–78. ACM Press, New York (2016)
Becker, R., Sagraloff, M., Sharma, V., Yap, C.: A near-optimal subdivision algorithm for complex root isolation based on the Pellet test and Newton iteration. J. Symb. Comput. 86, 51–96 (2018)
Ben-Or, M., Tiwari, P.: Simple algorithms for approximating all roots of a polynomial with real roots. J. Complex. 6(4), 417–442 (1990)
Du, Q., Jin, M., Li, T.Y., Zeng, Z.: The quasi-Laguerre iteration. Math. Comput. 66(217), 345–361 (1997)
Delves, L.M., Lyness, J.N.: A numerical method for locating the zeros of an analytic function. Math. Comput. 21, 543–560 (1967)
Demeure, C.J., Mullis, C.T.: The Euclid algorithm and the fast computation of cross-covariance and autocovariance sequences. IEEE Trans. Acoust. Speech Signal Process. 37, 545–552 (1989)
Demeure, C.J., Mullis, C.T.: A Newton-Raphson method for moving-average spectral factorization using the Euclid algorithm. IEEE Trans. Acoust. Speech Signal Process. 38, 1697–1709 (1990)
Ehrlich, L.W.: A modified Newton method for polynomials. Commun. ACM 10, 107–108 (1967)
Emiris, I.Z., Pan, V.Y., Tsigaridas, E.: Algebraic algorithms. In: Tucker, A.B., Gonzales, T., Diaz-Herrera, J.L. (eds.) Computing Handbook. Computer Science and Software Engineering, 3rd edn., vol. I, Chap. 10, pp. 10-1–10-40. Taylor and Francis Group (2014)
Fortune, S.: J. Symbol. Comput. 33(5), 627–646 (2002). Proc. version in Proc. Intern. Symp. on Symbolic and Algebraic Computation An Iterated Eigenvalue Algorithm for Approximating Roots of Univariate Polynomials, (ISSAC 2001), 121–128, ACM Press, New York (2001)
Householder, A.S.: Dandelin, Lobachevskii, or Graeffe? Amer. Math. Mon. 66, 464–466 (1959)
Henrici, P.: Applied and computational complex analysis. In: Power Series, Integration, Conformal Mapping, Location of Zeros, vol. 1. Wiley, New York (1974)
Henrici, P., Gargantini, I.: Uniformly convergent algorithms for the simultaneous approximation of all zeros of a polynomial. In: Dejon, B., Henrici, P. (eds.) Constructive Aspects of the Fundamental Theorem of Algebra. Wiley, New York (1969)
Imbach, R., Pan, V.Y., Yap, C.: Implementation of a near-optimal complex root clustering algorithm. In: Davenport, J.H., Kauers, M., Labahn, G., Urban, J. (eds.) ICMS 2018. LNCS, vol. 10931, pp. 235–244. Springer, Cham (2018). https://doi.org/10.1007/978-3-319-96418-8_28
Inbach, R., Pan, V.Y., Yap, C., Kotsireas, I.S., Zaderman, V.: Root-finding with implicit deflation. In: Proceedings CASC 2019. arxiv:1606.01396. Accepted 21 May 2019
Kirrinnis, P.: Polynomial factorization and partial fraction decomposition by simultaneous Newton’s iteration. J. Complex. 14, 378–444 (1998)
Kobel, A., Rouillier, F., Sagraloff, M.: Computing real roots of real polynomials ... and now for real! In: The International Symposium on Symbolic and Algebraic Computation (ISSAC 2016), pp. 301–310. ACM Press, New York (2016)
McNamee, J.M.: Numerical Methods for Roots of Polynomials, Part I, p. XIX+354. Elsevier, Amsterdam (2007)
Moenck, R., Borodin, A.: Fast modular transforms via division., In: Proceedings of 13th Annual Symposium on Switching and Automata Theory (SWAT 1972), pp. 90–96. IEEE Computer Society Press (1972)
McNamee, J.M., Pan, V.Y.: Numerical Methods for Roots of Polynomials, Part II, p. XXI+728. Elsevier, Amsterdam (2013)
Neff, C.A., Reif, J.H.: An \(o(n^{1 +\epsilon })\) algorithm for the complex root problem. In: Proceedings 35th Annual Symposium on Foundations of Computer Science (FOCS 1994), pp. 540–547. IEEE Computer Society Press (1994)
Pan, V.Y.: Optimal (up to polylog factors) sequential and parallel algorithms for approximating complex polynomial zeros. In: Proceedings of 27th Annual ACM Symposium on Theory of Computing (STOC 1995), pp. 741–750. ACM Press, New York (1995)
Pan, V.Y.: Solving a polynomial equation: some history and recent progress. SIAM Rev. 39(2), 187–220 (1997)
Pan, V.Y.: Solving polynomials with computers. Am. Sci. 86, 62–69 (1998)
Pan, V.Y.: Approximation of complex polynomial zeros: modified quadtree (Weyl’s) construction and improved Newton’s iteration. J. Complex. 16(1), 213–264 (2000)
Pan, V.Y.: Structured Matrices and Polynomials: Unified Superfast Algorithms. Birkhäuser/Springer, Boston/New York (2001). https://doi.org/10.1007/978-1-4612-0129-8
Pan, V.Y.: Univariate polynomials: nearly optimal algorithms for factorization and rootfinding. J. Symb. Comput. 33(5), 701–733 (2002)
Pan, V.Y.: Transformations of matrix structures work again. Linear Algebra Appl. 465, 1–32 (2015)
Pan, V.Y.: Root-finding with Implicit Deflation. arXiv:1606.01396, Accepted 4 June 2016
Pan, V.Y.: Simple and nearly optimal polynomial root-finding by means of root radii approximation. In: Kotsireas, I., Martinez-Moro, E. (eds.) ACA 2015. SPMS, vol. 198, pp. 329–340. Springer, Cham (2017). https://doi.org/10.1007/978-3-319-56932-1_23
Pan, V.Y.: Fast approximate computations with Cauchy matrices and polynomials. Math. Comput. 86, 2799–2826 (2017)
Pan, V.Y.: Old and new nearly optimal polynomial root-finders, In: Proceedings of CASC (2019). Also arxiv: 1805.12042 May 2019
Pan, V.Y., Sadikou, A., Landowne, E.: Univariate polynomial division with a remainder by means of evaluation and interpolation. In: Proceedings of 3rd IEEE Symposium on Parallel and Distributed Processing, pp. 212–217. IEEE Computer Society Press, Los Alamitos (1991)
Pan, V.Y., Sadikou, A., Landowne, E.: Polynomial division with a remainder by means of evaluation and interpolation. Inform. Process. Lett. 44, 149–153 (1992)
Pan, V.Y., Tsigaridas, E.P.: Nearly optimal refinement of real roots of a univariate polynomial. J. Symb. Comput. 74, 181–204 (2016). Proceedings version. In: Kauers, M. (ed.) Proc. ISSAC 2013, pp. 299–306. ACM Press, New York (2013)
Pan, V.Y., Tsigaridas, E.P.: Nearly optimal computations with structured matrices. Theor. Comput. Sci. 681, 117–137 (2017)
Pan, V.Y., Zhao, L.: Real root isolation by means of root radii approximation. In: Gerdt, V.P., Koepf, W., Seiler, W.M., Vorozhtsov, E.V. (eds.) CASC 2015. LNCS, vol. 9301, pp. 349–360. Springer, Heidelberg (2015). https://doi.org/10.1007/978-3-319-24021-3_26
Pan, V.Y., Zhao, L.: Real polynomial root-finding by means of matrix and polynomial iterations. Theor. Comput. Sci. 681, 101–116 (2017)
Renegar, J.: On the worst-case arithmetic complexity of approximating zeros of polynomials. J. Complex. 3(2), 90–113 (1987)
Schönhage, A.: The Fundamental Theorem of Algebra in Terms of Computational Complexity. Department of Mathematics. University of Tübingen, Tübingen, Germany (1982)
Schönhage, A.: Asymptotically fast algorithms for the numerical muitiplication and division of polynomials with complex coefficients. In: Calmet, J. (ed.) EUROCAM 1982. LNCS, vol. 144, pp. 3–15. Springer, Heidelberg (1982). https://doi.org/10.1007/3-540-11607-9_1
Schönhage, A.: Quasi GCD computations. J. Complex. 1, 118–137 (1985)
Schleicher, D.: Private communication (2018)
Schleicher, D., Stoll, R.: Newton’s method in practice: finding all roots of polynomials of degree one million efficiently. Theor. Comput. Sci. 681, 146–166 (2017)
Tilli, P.: Convergence conditions of some methods for the simultaneous computation of polynomial zeros. Calcolo 35, 3–15 (1998)
Van Dooren, P.: Some numerical challenges in control theory. In: Van Dooren, P., Wyman, B. (eds.) Linear Algebra for Control Theory. The IMA Volumes in Mathematics and its Applications, vol. 62. Springer, New York (1994). https://doi.org/10.1007/978-1-4613-8419-9_12
Weierstrass, K.: Neuer Beweis des Fundamentalsatzes der Algebra. Mathematische Werke, Bd, vol. III, pp. 251–269. Mayer und Mueller, Berlin (1903)
Weyl, H.: Randbemerkungen zu Hauptproblemen der Mathematik. II. Fundamentalsatz der Algebra und Grundlagen der Mathematik. Math. Z. 20, 131–151 (1924)
Wilson, G.T.: Factorization of the covariance generating function of a pure moving-average. SIAM J. Numer. Anal. 6, 1–7 (1969)
Werner, W.: Some improvements of classical iterative methods for the solution of nonlinear equations. In: Allgower, E.L., Glashoff, K., Peitgen, H.-O. (eds.) Numerical Solution of Nonlinear Equations. LNM, vol. 878, pp. 426–440. Springer, Heidelberg (1981). https://doi.org/10.1007/BFb0090691
Acknowledgements
This research has been supported by NSF Grants CCF–1563942 and CCF–1733834 and PSC CUNY Award 69813 00 48.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2019 Springer Nature Switzerland AG
About this paper
Cite this paper
Pan, V.Y. (2019). Old and New Nearly Optimal Polynomial Root-Finders. In: England, M., Koepf, W., Sadykov, T., Seiler, W., Vorozhtsov, E. (eds) Computer Algebra in Scientific Computing. CASC 2019. Lecture Notes in Computer Science(), vol 11661. Springer, Cham. https://doi.org/10.1007/978-3-030-26831-2_26
Download citation
DOI: https://doi.org/10.1007/978-3-030-26831-2_26
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-030-26830-5
Online ISBN: 978-3-030-26831-2
eBook Packages: Computer ScienceComputer Science (R0)