The goal of this paper is to approach exact (roundoff error free) algorithms for geometric manipulation of geographical data. The main focus of this article is the map overlay algorithm, having TerraLib, a spatial component library with geometric algorithms support, as a development environment. Resumo. O objetivo deste trabalho é abordar algoritmos exatos (livre de erros de arredondamento) par...

Many system types in engineering require mathematical models involving non-differentiable or discontinuous functions. Such system models are often sensitive to round-off errors. Their parameters might be uncertain due to impreciseness in measurements or lack of knowledge. Therefore, interval methods represent a straightforward choice for verified analysis of such systems. However, application o...

We show several ways to round a real matrix to an integer one such that the rounding errors in all rows and columns as well as the whole matrix are less than one. This is a classical problem with applications in many fields, in particular, statistics. We improve earlier solutions of different authors in two ways. For rounding matrices of size m × n, we reduce the runtime from O((mn)) to O(mn lo...

In many multimedia applications, manipulation of video signals is preferably performed in the transform domain. Most of such operations are derived from their counterparts in the pixel domain. However, the rounding operation can not be obtained this way because it is a nonlinear operation. Without a proper treatment, it may become a major source of errors for multimedia systems, causing a misma...

Abstract. We construct, analyze and numerically validate a class of conservative, discontinuous Galerkin schemes for the Generalized Korteweg-de Vries equation. Up to round-off error, these schemes preserve discrete versions of the first two invariants (the integral of the solution, usually identified with the mass, and the L–norm) of the continuous solution. Numerical evidence is provided indi...

A new criterion for selective reorthogonalization in the modified Gram–Schmidt algorithm is proposed. We study its behavior in the presence of rounding errors. We give some counterexample matrices which prove that the standard criteria might fail. Through numerical experiments, we illustrate that our new criterion seems to be suitable also for the classical Gram– Schmidt algorithm with selectiv...

quickpsy is a package to parametrically fit psychometric functions. In comparison with previous R packages, quickpsy was built to easily fit and plot data for multiple groups. Here, we describe the standard parametric model used to fit psychometric functions and the standard estimation of its parameters using maximum likelihood. We also provide examples of usage of quickpsy, including how allow...

Measuring the rate of return is an important issue for theory and practice of investments in the stock market. A common measure for rate of return is the logarithm of the ratio of successive prices (LogRatio). In this paper it is shown that LogRatio as well as arithmetic return rate (Ratio) have several disadvantages. As an alternative relative differences (RelDiff) are proposed to measure retu...

The paper considers four algorithms arising in the parameters correctly, but can exhibit a bursting adaptive systems problems, equation error identification, output phenomenon, lts output can, as a result of noise, error identification, reference trajectory following and adaptive ole oositionine Theoretical exn~anation hacked hv nonlinearities, round-off errors and so on, exhibit . . ~~~~~~~~ ~...

High-order derivatives of analytic functions are expressible as Cauchy integrals over circular contours, which can very effectively be approximated, e.g., by trapezoidal sums. Whereas analytically each radius r up to the radius of convergence is equal, numerical stability strongly depends on r . We give a comprehensive study of this effect; in particular, we show that there is a unique radius t...