Superfast inversion of two-level Toeplitz matrices using Newton iteration and tensor-displacement structure
نویسندگان
چکیده
A fast approximate inversion algorithm is proposed for two-level Toeplitz matrices (block Toeplitz matrices with Toeplitz blocks). It applies to matrices that can be sufficiently accurately approximated by matrices of low Kronecker rank and involves a new class of tensor-displacement-rank structured (TDS) matrices. The complexity depends on the prescribed accuracy and typically is o(n) for matrices of order n.
منابع مشابه
New Approach for the Inversion of Structured Matrices via Newton’s Iteration
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