As a contribution to computer drawing especially of pieces of surfaces of higher order three versions of an ALGOL-program are presented. They permit to draw to net of parameter curves or a pair of picture for stereosc...
详细信息
As a contribution to computer drawing especially of pieces of surfaces of higher order three versions of an ALGOL-program are presented. They permit to draw to net of parameter curves or a pair of picture for stereoscopic viewing or of a picture of the surface with hidden lines suppressed; the input information requested is kept at a minimum. For the hidden line problem a method is *** program is intended for use in pure mathematics particularly in differential geometry.
The problem of orthogonal linear regression [1, 2] to connect a number ofn pointsP i (x i ,y i ) ∈R×R by a regression lineg in such a way that the orthogonal distance of these pointsP i from the line is minimize...
详细信息
The problem of orthogonal linear regression [1, 2] to connect a number ofn pointsP i (x i ,y i ) ∈R×R by a regression lineg in such a way that the orthogonal distance of these pointsP i from the line is minimized by the method of least squares is very easy to solve if each pointP i is correlated with the complex numberz i =x i +jy i . The associated algorithm is expressed in FORTRAN IV.
In this paper we consider in a domainG ofRn a family of quasilinear elliptic boundary value problems and their finite element solutions with piecewise linear trial functions. A simple geometrical condition ensures, th...
详细信息
In this paper we consider in a domainG ofRn a family of quasilinear elliptic boundary value problems and their finite element solutions with piecewise linear trial functions. A simple geometrical condition ensures, that any such solution assumes its maximum and minimum at points on the boundary ofG.
In [3] a set of procedures is given for simulating interval-arthmetic on ALGOL-60 compilers. The present paper describes ALGOL-60 procedures evaluating standard functions in interval analysis in connection with the pr...
详细信息
In [3] a set of procedures is given for simulating interval-arthmetic on ALGOL-60 compilers. The present paper describes ALGOL-60 procedures evaluating standard functions in interval analysis in connection with the procedures mentioned. A short theoretical introduction to the problem is given.
作者：
STREHMEL, KPEPER, CSektion Mathematik
Martin-Luther-Universität Halle-Wittenberg Weinbergweg 17 DDR-402 Halle a. d. Saale Deutsche Demokratische Republik
In the present paper a new exponentially fitted one-step method is given for the numerical treatment of the initial value problemy(n)=f(x, y, y′, ..., y(n−1)),y(j) (x0)=y (j)0 j=0, 1, ...n−1. The method is given by a...
详细信息
In the present paper a new exponentially fitted one-step method is given for the numerical treatment of the initial value problemy(n)=f(x, y, y′, ..., y(n−1)),y(j) (x0)=y (j)0 j=0, 1, ...n−1. The method is given by a local linearisation off(x, y, y′, ..., y(n−1)). Using new functions the solution of a special linear differential equation of then-th order with constant coefficients is transformed in such a way so that it no longer contains numerical singularities. The efficiency of the method is demonstrated by several numerical stiff-examples.
By means of abstract models we consider systems, that are represented by subjects, objects and the two subject-object-relations “read” and “modify”. The possible structures in a system, that guarantees the privacy...
详细信息
By means of abstract models we consider systems, that are represented by subjects, objects and the two subject-object-relations “read” and “modify”. The possible structures in a system, that guarantees the privacy of data, are examined. The relation between the models and the real world is shown by some examples.
For nonlinear SOR-methods (Newton-SOR-methods) we discuss the problem how to get asymptotic optimal relaxation parameters ω(v). Here the matrix of the linear system at each step of iteration has not to be consistentl...
详细信息
For nonlinear SOR-methods (Newton-SOR-methods) we discuss the problem how to get asymptotic optimal relaxation parameters ω(v). Here the matrix of the linear system at each step of iteration has not to be consistently ordered, we only assume symmetry and definitness. Our parameters are easy to compute and fixed for all steps. As an example nonlinear elliptic differential equations and their numerical solution by the finite element method or classical difference approximation are considered.
This note presents a matrix representation of iterative methods which is a generalization of those given by Miranker [6] and Rice [8]. It is based on an elementary theorem which show that the order of convergence of s...
详细信息
This note presents a matrix representation of iterative methods which is a generalization of those given by Miranker [6] and Rice [8]. It is based on an elementary theorem which show that the order of convergence of some nonlinear single-step and total-step methods is the spectral radius of a certain matrix. Thus a large class of iterative methods are easy to analyze especially such as: Hermiteinterpolatory methods, composite Hermite-interpolatory methods, several parallel methods and even special methods for systems of equations.
暂无评论