Matrix: ND/nd3k

Description: ND problem set, matrix nd3k

ND/nd3k graph
(undirected graph drawing)


ND/nd3k

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  • Matrix group: ND
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  • download as a MATLAB mat-file, file size: 24 MB. Use UFget(936) or UFget('ND/nd3k') in MATLAB.
  • download in Matrix Market format, file size: 13 MB.
  • download in Rutherford/Boeing format, file size: 11 MB.

    Matrix properties
    number of rows9,000
    number of columns9,000
    nonzeros3,279,690
    structural full rank?yes
    structural rank9,000
    # of blocks from dmperm1
    # strongly connected comp.1
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typereal
    structuresymmetric
    Cholesky candidate?yes
    positive definite?yes

    authorauthor unknown
    editorT. Davis
    date2003
    kind2D/3D problem
    2D/3D problem?yes

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD15,894,180
    Cholesky flop count3.7e+10
    nnz(L+U), no partial pivoting, with AMD31,779,360
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD13,949,445
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD27,269,737

    SVD-based statistics:
    norm(A)127.6
    min(svd(A))8.1423e-06
    cond(A)1.56713e+07
    rank(A)9,000
    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

    ND/nd3k 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.