Matrix: Nemeth/nemeth18

Description: Newton-Schultz iteration, Z_k+1=Z_k+(1/2)*(I-(Z_k)^2)*Z_k. This is Z_18

Nemeth/nemeth18 graph
(undirected graph drawing)


Nemeth/nemeth18

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  • Matrix group: Nemeth
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  • download as a MATLAB mat-file, file size: 5 MB. Use UFget(782) or UFget('Nemeth/nemeth18') in MATLAB.
  • download in Matrix Market format, file size: 4 MB.
  • download in Rutherford/Boeing format, file size: 4 MB.

    Matrix properties
    number of rows9,506
    number of columns9,506
    nonzeros695,234
    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/nemeth19 first: Nemeth/nemeth01
    

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD382,022
    Cholesky flop count1.5e+07
    nnz(L+U), no partial pivoting, with AMD754,538
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD383,290
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD751,356

    SVD-based statistics:
    norm(A)0.925531
    min(svd(A))0.218339
    cond(A)4.23897
    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/nemeth18 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.