Experiments with a Weakly Stable Algorithm for Computing
Pade'-Hermite and Simultaneous Pade' Approximants
S. Cabay, A. Jones and G. Labahn
Abstract
In a recent paper, the authors have developed a fast, iterative, look-ahead
algorithm for numerically computing Pade'-Hermite systems and simultaneous
Pade' systems along a diagonal of the associated Pade' tables.
Included there is a detailed error analysis showing that the algorithm is
weakly stable.
In this paper, we describe a Fortran implementation, VECTOR_PADE, of this
algorithm together with a number of numerical experiments.
These experiments show that the theoretical error bounds reflect the general
behavior of the actual error, but that in practice these bounds are large
over-estimates.
The complete
document
can be retrieved by anonymous ftp at
ftp.cs.ualberta.ca/pub/cabay/experiments_pade_alg.ps.Z
The
fortran 77 code for VECTOR_PADE is available by
anonymous ftp at ftp.cs.ualberta.ca/pub/cabay/pade_software/vector_pade