منابع مشابه
Groups of banded matrices with banded inverses
AproductADF1 : : : FN of invertible block-diagonalmatrices will be bandedwith a banded inverse. We establish this factorization with the numberN controlled by the bandwidthsw and not by the matrix size n:When A is an orthogonal matrix, or a permutation, or banded plus finite rank, the factors Fi have w D 1 and generate that corresponding group. In the case of infinite matrices, conjectures rema...
متن کاملThe Asymptotic Spectra of Banded Toeplitz and Quasi-Toeplitz Matrices
Toeplitz matrices occur in many mathematical as well as scientific and engineering investigations. This paper considers the spectra of banded Toeplitz and quasi-Toeplitz matrices with emphasis on non-normal matrices of arbitrarily large order and relatively small bandwidth. These are the type of matrices that appear in the investigation of stability and convergence of difference approximations ...
متن کاملFast transforms: Banded matrices with banded inverses.
It is unusual for both A and A(-1) to be banded--but this can be a valuable property in applications. Block-diagonal matrices F are the simplest examples; wavelet transforms are more subtle. We show that every example can be factored into A = F(1)...F(N) where N is controlled by the bandwidths of A and A(-1) (but not by their size, so this extends to infinite matrices and leads to new matrix gr...
متن کاملProperties of Oh/ir Stars with the Iras Lrs Spectra
1607 OH/IR stars associated with IRAS sources are assembled and the IRAS LRS spectra of 980 OH/IR stars are examined in this paper. The nature of the circumstellar dust for these sources is classiied. The distributions of these subgroups of OH/IR stars in the IRAS color{color diagram and the period{color diagram are interpreted with their evolutionary status. The Galactic and the velocity distr...
متن کاملCircumstellar Molecular Spectra towards Evolved Stars
In this paper we discuss the relevance of, and possible scientific gains which can be acquired from studying circumstellar molecular spectra toward evolved stars. Where can we expect circumstellar molecular spectra, why would we want to study these spectra, which molecules might be present, and what can we learn from these studies? We present an overview of reported detections, and discuss some...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Nature
سال: 1886
ISSN: 0028-0836,1476-4687
DOI: 10.1038/033583d0