Factorizations of matrices and functions of two variables
Fast and correctly rounded logarithms in double-precision
This article is a case study in the implementation of a portable, proven and efficient correctly rounded elementary function in double-precision. We describe the methodology used to achieve these goals in the crlibm library. There are two novel aspects to this approach. The first is the proof framework, and in general the techniques used to balance performance and provability. The second is the introduction of processor-specific optimization to get performance equivalent to the best current...
Fast evaluation of thin-plate splines on fine square grids
The paper deals with effective calculation of Thin-Plate Splines (TPS). We present a new modification of hierarchical approximation scheme. Unlike 2-D schemes published earlier, we propose an 1-D approximation. The new method yields lower computing complexity while it preserves the approximation accuracy.
Fast Leja points.
Fast multilevel evaluation of smooth radial basis function expansions.
Fast Toeplitz Orthogonalization.
Fehlerabschätzungen für Gauß-Quadraturformeln.
Fehlerabschätzungen für Koeffizienten von Exponentialsummen und Polynomen.
Fehlerabschätzungen für nichtsymmetrische Gauß-Quadraturformeln.
Finding discontinuities of piecewise-smooth functions.
Finite element derivative interpolation recovery technique and superconvergence
A new finite element derivative recovery technique is proposed by using the polynomial interpolation method. We show that the recovered derivatives possess superconvergence on the recovery domain and ultraconvergence at the interior mesh points for finite element approximations to elliptic boundary problems. Compared with the well-known Z-Z patch recovery technique, the advantage of our method is that it gives an explicit recovery formula and possesses the ultraconvergence for the odd-order finite...
Finite volume schemes for the generalized subjective surface equation in image segmentation
In this paper, we describe an efficient method for 3D image segmentation. The method uses a PDE model – the so called generalized subjective surface equation which is an equation of advection-diffusion type. The main goal is to develop an efficient and stable numerical method for solving this problem. The numerical solution is based on semi-implicit time discretization and flux-based level set finite volume space discretization. The space discretization is discussed in details and we introduce three...
Finite-element discretizations of a two-dimensional grade-two fluid model
We propose and analyze several finite-element schemes for solving a grade-two fluid model, with a tangential boundary condition, in a two-dimensional polygon. The exact problem is split into a generalized Stokes problem and a transport equation, in such a way that it always has a solution without restriction on the shape of the domain and on the size of the data. The first scheme uses divergence-free discrete velocities and a centered discretization of the transport term, whereas the other schemes...
Finite-element discretizations of a two-dimensional grade-two fluid model
We propose and analyze several finite-element schemes for solving a grade-two fluid model, with a tangential boundary condition, in a two-dimensional polygon. The exact problem is split into a generalized Stokes problem and a transport equation, in such a way that it always has a solution without restriction on the shape of the domain and on the size of the data. The first scheme uses divergence-free discrete velocities and a centered discretization of the transport term, whereas the other schemes...
Fitting a -Smooth Function to Data II.
Fitting scattered data on spherelike surfaces using tensor products of trigonometric and polynomial splines.
Fonctions «spline» et méthode d'éléments finis
Formally certified floating-point filters for homogeneous geometric predicates
Floating-point arithmetic provides a fast but inexact way of computing geometric predicates. In order for these predicates to be exact, it is important to rule out all the numerical situations where floating-point computations could lead to wrong results. Taking into account all the potential problems is a tedious work to do by hand. We study in this paper a floating-point implementation of a filter for the orientation-2 predicate, and how a formal and partially automatized verification of this...
Formation of Singularities in Fluid Interfaces
Formulas for Best Extrapolation.