Matrix: Meszaros/iprob

Description: Problematic linear programming problem, Meszaros test set

Meszaros/iprob graph
(undirected graph drawing)


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  • Matrix group: Meszaros
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  • download as a MATLAB mat-file, file size: 41 KB. Use UFget(1790) or UFget('Meszaros/iprob') in MATLAB.
  • download in Matrix Market format, file size: 41 KB.
  • download in Rutherford/Boeing format, file size: 41 KB.

    Matrix properties
    number of rows3,001
    number of columns3,001
    structural full rank?yes
    structural rank3,001
    # of blocks from dmperm1
    # strongly connected comp.1
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetry 50%
    Cholesky candidate?no
    positive definite?no

    editorC. Meszaros
    kindlinear programming problem
    2D/3D problem?no

    Additional fieldssize and type
    bfull 3001-by-1
    cfull 3001-by-1
    lofull 3001-by-1
    hifull 3001-by-1
    z0full 1-by-1

    Converted to standard form via Resende and Veiga's mpsrd:
    minimize c'*x, subject to A*x=b and lo <= x <= hi        

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD6,001
    Cholesky flop count1.2e+04
    nnz(L+U), no partial pivoting, with AMD9,001
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD6,001
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD4,504,501

    SVD-based statistics:
    null space dimension1
    full numerical rank?no
    singular value gap3.18999e+16

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

    Meszaros/iprob 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.