Fast transforms: Banded matrices with banded inverses.

نویسنده

  • Gilbert Strang
چکیده

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 groups).

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عنوان ژورنال:
  • Proceedings of the National Academy of Sciences of the United States of America

دوره 107 28  شماره 

صفحات  -

تاریخ انتشار 2010