Computing rational forms of integer matrices

  • Authors:
  • Mark Giesbrecht;Arne Storjohann

  • Affiliations:
  • School of Computer Science, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1;School of Computer Science, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1

  • Venue:
  • Journal of Symbolic Computation
  • Year:
  • 2002

Quantified Score

Hi-index 0.00

Visualization

Abstract

A new algorithm is presented for finding the Frobenius rational form F ∈ Zn×n of any A ∈ Zn×n which requires an expected number of O(n4(logn + log ||A||) + n3(log n + log ||A||)2) word operations using standard integer and matrix arithmetic (where ||A||= maxij |Aij|). This substantially improves on the fastest previously known algorithms. The algorithm is probabilistic of the Las Vegas type: it assumes a source of random bits but always produces the correct answer. Las Vegas algorithms are also presented for computing a transformation matrix to the Frobenius form, and for computing the rational Jordan form of an integer matrix.