منابع مشابه
Underspecified computation of normal forms
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This paper is about how to compute the Hermite normal form of a random integer matrix in practice. We propose significant improvements to the algorithm by Micciancio and Warinschi, and extend these techniques to the computation of the saturation of a matrix. Tables of timings confirm the efficiency of this approach. To our knowledge, our implementation is the fastest implementation for computin...
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Considering qualitative behavior of a non-linear dynamical system often leads to first simplifying the differential equations or finding their normal forms. A perturbation technique for computing normal forms is presented. This technique, associated with the method of multiple scales, can be used to systematically find a unique form for a given set of differential equations. The technique is di...
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Symmetry properties of r-times covariant tensors T can be described by certain linear subspaces W of the group ring K[Sr] of a symmetric group Sr. If for a class of tensors T such a W is known, the elements of the orthogonal subspace W⊥ of W within the dual space K[Sr] of K[Sr] yield linear identities needed for a treatment of the term combination problem for the coordinates of the T . We give ...
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ژورنال
عنوان ژورنال: Journal of Computational and Applied Mathematics
سال: 1990
ISSN: 0377-0427
DOI: 10.1016/0377-0427(90)90353-2