In this paper a convergence proof is given for the continuous analog of the Gauss—Newton method for nonlinear ill-posed operator equations and convergence rates are obtained. Convergence for exact data is proved for nonmonotone operators under weaker source conditions than before. Moreover, nonlinear ill-posed problems with noisy data are considered and a priori and a posteriori stopping rules ...

Exact values are derived for some matrix elements of Lagrange functions, i.e. orthonormal cardinal functions, constructed from orthogonal polynomials. They are obtained with exact Gauss quadratures supplemented by corrections. In the particular case of Lagrange-Laguerre and shifted Lagrange-Jacobi functions, sum rules provide exact values for matrix elements of 1/x and 1/x as well as for the ki...

in the 1960's noboru iwahori and hideya matsumoto, eiichi abe and kazuo suzuki, and michael stein discovered that chevalley groups $g=g(phi,r)$ over a semilocal ring admit remarkable gauss decomposition $g=tuu^-u$, where $t=t(phi,r)$ is a split maximal torus, whereas $u=u(phi,r)$ and $u^-=u^-(phi,r)$ are unipotent radicals of two opposite borel subgroups $b=b(phi,r)$ and $b^-=b^-(phi,r)$ contai...

It is well known that integration formulas of precision 2fc (2fc + 1) for a region in n-space which is a Cartesian product of intervals can be obtained from onedimensional Radau (Gauss) rules. The number of function evaluations in these product cubatures is (fc + 1) . In this paper, an algorithm is given for obtaining cubatures for hyperrectangles in n-space of precision 2fc, in many instances ...

Abstract In this paper we consider some rational approximations to the fractional powers of self-adjoint positive operators, arising from Gauss–Laguerre rules. We derive practical error estimates that can be used select a priori number Laguerre points necessary achieve given accuracy. also present numerical experiments show effectiveness our approaches and reliability estimates.

We use the periodicity properties of generalized Gauss sums to factor numbers. Moreover, we derive rules for finding the factors and illustrate this factorization scheme for various examples. This algorithm relies solely on interference and scales exponentially. 4 Author to whom any correspondence should be addressed. New Journal of Physics 13 (2011) 103007 1367-2630/11/103007+37$33.00 © IOP Pu...

Abstract. Let dμ be a nonnegative measure with support on the real axis and let α ∈ R be outside the convex hull of the support. This paper describes a new approach to determining recursion coefficients for Gauss quadrature rules associated with measures of the form dμ̌(x) := dμ(x)/(x − α)2l. The proposed method is based on determining recursion coefficients for a suitable family of orthonormal ...

We survey some unusual eigenvalue problems arising in different applications. We show that all these problems can be cast as problems of estimating quadratic forms. Numerical algorithms based on the well-known Gauss-type quadrature rules and Lanczos process are reviewed for computing these quadratic forms. These algorithms reference the matrix in question only through a matrix-vector product op...

Nyström method is a standard numerical technique to solve Fredholm integral equations of the second kind where integration kernel approximated using quadrature formula. Traditionally, rule used classical polynomial Gauss quadrature. Motivated by observation that given function can be better spline lower degree than single piece higher degree, in this work, we investigate use Gaussian rules for ...