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MiS Preprint

Variational Calculus with Sums of Elementary Tensors of Fixed Rank

Mike Espig, Wolfgang Hackbusch, Thorsten Rohwedder and Reinhold Schneider


In this article we introduce a calculus of variations for sums of elementary tensors and apply it to functionals of practical interest. The survey provides all necessary ingredients for applying minimization methods in a general setting. The important cases of target functionals which are linear and quadratic with respect to the tensor product are discussed, and combinations of these functionals are presented in detail. As an example, we consider the solution of a linear system in structured tensor format. Moreover, we discuss the solution of an eigenvalue problem with sums of elementary tensors. This example can be viewed as a prototype of a constrained minimization problem. For the numerical treatment, we suggest a method which has the same order of complexity as the popular alternating least square algorithm and demonstrate the rate of convergence in numerical tests.

Aug 28, 2009
Aug 28, 2009

Related publications

2012 Repository Open Access
Mike Espig, Wolfgang Hackbusch, Thorsten Rohwedder and Reinhold Schneider

Variational calculus with sums of elementary tensors of fixed rank

In: Numerische Mathematik, 122 (2012) 3, pp. 469-488