10 citations · 18 across the 6 of their papers we have counts for
5 papers · 1 filter
Design of accurate formulas for approximating functions in weighted Hardy spaces by discrete energy minimization
Ken'ichiro Tanaka, Masaaki Sugihara
We propose a simple and effective method for designing approximation formulas for weighted analytic functions. We consider spaces of such functions according to weight functions ex…
An optimal approximation formula for functions with singularities
Ken'ichiro Tanaka, Tomoaki Okayama, Masaaki Sugihara
We propose an optimal approximation formula for analytic functions that are defined on a complex region containing the real interval and possibly have algebraic singularit…
Structure of the preconditioned system in various preconditioned conjugate gradient squared algorithms
Shoji Itoh, Masaaki Sugihara
An improved preconditioned conjugate gradient squared (PCGS) algorithm has recently been proposed, and it performs much better than the conventional PCGS algorithm. In this paper,…
Structure of the polynomials in preconditioned BiCG algorithms and the switching direction of preconditioned systems
Shoji Itoh, Masaaki Sugihara
We present a theorem that defines the direction of a preconditioned system for the bi-conjugate gradient (BiCG) method, and we extend it to preconditioned bi-Lanczos-type algorithm…
Potential theoretic approach to design of accurate formulas for function approximation in symmetric weighted Hardy spaces
Ken'ichiro Tanaka, Tomoaki Okayama, Masaaki Sugihara
We propose a method for designing accurate interpolation formulas on the real axis for the purpose of function approximation in weighted Hardy spaces. In particular, we consider th…