منابع مشابه
The Radau-Lanczos Method for Matrix Functions
Analysis and development of restarted Krylov subspace methods for computing f(A)b have proliferated in recent years. We present an acceleration technique for such methods when applied to Stieltjes functions f and Hermitian positive definite matrices A. This technique is based on a rank-one modification of the Lanczos matrix derived from a connection between the Lanczos process and Gauss–Radau q...
متن کاملGeneralized Gauss – Radau and Gauss – Lobatto Formulae ∗
Computational methods are developed for generating Gauss-type quadrature formulae having nodes of arbitrary multiplicity at one or both end points of the interval of integration. Positivity properties of the boundary weights are investigated numerically, and related conjectures are formulated. Applications are made to moment-preserving spline approximation. AMS subject classification: 65D30.
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We consider the behaviour of the cosmological acceleration for timedependent hyperbolic and flux compactifications of M-theory, with an exponential potential. For flat and closed cosmologies it is seen that a positive acceleration is always transient for both compactifications. For open cosmologies, both compactifications can give at late times periods of positive acceleration. As a function of...
متن کاملGauss-Radau Quadrature Rule Using Special Class of Polynomials
A form of Gauss-Quadrature rule over [0,1] has been investigated that involves the derivative of the integrand at the pre-assigned left or right end node. This situation arises when the underlying polynomials are orthogonal with respect to the weight function (): 1 x x ω = − over [0,1]. Along the lines of Golub's work, the nodes and weights of the quadrature rule are computed from a Jacobi-type...
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ژورنال
عنوان ژورنال: Nature
سال: 1912
ISSN: 0028-0836,1476-4687
DOI: 10.1038/088414d0