Title
Computing Canonical Bases of Modules of Univariate Relations.
Abstract
We study the computation of canonical bases of sets of univariate relations (p1,...,pm) ∈ K[x]m such that p1 f1 + ⋯ + pm fm = 0; here, the input elements f1,...,fm are from a quotient K[x]n/M, where M is a K[x]-module of rank n given by a basis M ∈ K[x]n x n in Hermite form. We exploit the triangular shape of M to generalize a divide-and-conquer approach which originates from fast minimal approximant basis algorithms. Besides recent techniques for this approach, we rely on high-order lifting to perform fast modular products of polynomial matrices of the form P F mod M. Our algorithm uses O~(mω-1D + nω D/m) operations in K, where D = deg(det(M)) is the K-vector space dimension of K[x]n/M, O~(·) indicates that logarithmic factors are omitted, and ω is the exponent of matrix multiplication. This had previously only been achieved for a diagonal matrix M. Furthermore, our algorithm can be used to compute the shifted Popov form of a nonsingular matrix within the same cost bound, up to logarithmic factors, as the previously fastest known algorithm, which is randomized.
Year
DOI
Venue
2017
10.1145/3087604.3087656
ISSAC
Keywords
DocType
Volume
Polynomial matrix, shifted Popov form, division with remainder, univariate equations, syzygy module
Conference
abs/1705.10649
Citations 
PageRank 
References 
3
0.40
17
Authors
2
Name
Order
Citations
PageRank
Vincent Neiger1397.22
Thi Xuan Vu230.40