Matrix: Nemeth/nemeth25

Description: Newton-Schultz iteration, Z_k+1=Z_k+(1/2)*(I-(Z_k)^2)*Z_k. This is Z_25

Nemeth/nemeth25 graph
(undirected graph drawing)


Nemeth/nemeth25

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  • Matrix group: Nemeth
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  • download as a MATLAB mat-file, file size: 12 MB. Use UFget(789) or UFget('Nemeth/nemeth25') in MATLAB.
  • download in Matrix Market format, file size: 9 MB.
  • download in Rutherford/Boeing format, file size: 8 MB.

    Matrix properties
    number of rows9,506
    number of columns9,506
    nonzeros1,511,758
    structural full rank?yes
    structural rank9,506
    # of blocks from dmperm1
    # strongly connected comp.1
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typereal
    structuresymmetric
    Cholesky candidate?no
    positive definite?no

    authorK. Nemeth
    editorT. Davis
    date1999
    kindsubsequent theoretical/quantum chemistry problem
    2D/3D problem?no

    Notes:

    next: Nemeth/nemeth26 first: Nemeth/nemeth01
    

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD798,379
    Cholesky flop count6.7e+07
    nnz(L+U), no partial pivoting, with AMD1,587,252
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD827,258
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD1,749,823

    SVD-based statistics:
    norm(A)1
    min(svd(A))0.999977
    cond(A)1.00002
    rank(A)9,506
    sprank(A)-rank(A)0
    null space dimension0
    full numerical rank?yes

    singular values (MAT file):click here
    SVD method used:s = svd (full (A)) ;
    status:ok

    Nemeth/nemeth25 svd

    For a description of the statistics displayed above, click here.

    Maintained by Tim Davis, last updated 12-Mar-2014.
    Matrix pictures by cspy, a MATLAB function in the CSparse package.
    Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.