On the Approximation of Pseudospectra of Nonnormal Operators by Discretization, Part I: the First Derivative Operator
نویسنده
چکیده
This paper is devoted to the study of the innuence of discretization schemes on the pseudospectrum of the rst derivative operator. Spectral and nite diierence methods are considered. Ample illustrations are provided which show the high sensitivity of the pseudospectrum to the chosen discretization method.
منابع مشابه
On the Approximation of Pseudospectra of Nonnormal Operators by Discretization, Part Ii: the Convection-diiusion Operator
In an earlier report 4], the pseudospectrum of the rst derivative operator discretized by spectral and nite diierence methods has been analyzed. Here, the same work is carried out for the convection-diiusion operator. The high sensitivity of the pseudospectrum of the operator under several discretization methods is illustrated by numerous examples.
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تاریخ انتشار 1997