Matrix: GHS_psdef/ldoor

Description: INDEED Test Matrix

GHS_psdef/ldoor graph
(undirected graph drawing)

GHS_psdef/ldoor dmperm of GHS_psdef/ldoor

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  • Matrix group: GHS_psdef
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  • download as a MATLAB mat-file, file size: 308 MB. Use UFget(1268) or UFget('GHS_psdef/ldoor') in MATLAB.
  • download in Matrix Market format, file size: 240 MB.
  • download in Rutherford/Boeing format, file size: 192 MB.

    Matrix properties
    number of rows952,203
    number of columns952,203
    structural full rank?yes
    structural rank952,203
    # of blocks from dmperm42,667
    # strongly connected comp.42,667
    explicit zero entries4,028,658
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    Cholesky candidate?yes
    positive definite?yes

    authorJ. Weiher
    editorJ. Koster
    kindstructural problem
    2D/3D problem?yes

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD141,363,607
    Cholesky flop count1.1e+11
    nnz(L+U), no partial pivoting, with AMD281,775,011
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD493,926,414
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD1,038,324,331

    Note that all matrix statistics (except nonzero pattern symmetry) exclude the 4028658 explicit zero entries.

    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.