• SJSU Singular Matrix Database
  • Matrix group: Meszaros
  • Click here for a description of the Meszaros group.
  • Click here for a list of all matrices
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  • Matrix: Meszaros/aa4
  • Description: linear programming problem, C. Meszaros test set
  • download as a MATLAB mat-file, file size: 70 KB. Use SJget(446) or SJget('Meszaros/aa4') in MATLAB.
  • download in Matrix Market format, file size: 135 KB.
  • download in Rutherford/Boeing format, file size: 74 KB.

    Meszaros/aa4

    Routine svd from Matlab 7.6.0.324 (R2008a) used to calculate the singular values.

    Meszaros/aa4

    Matrix properties (click for a legend)  
    number of rows426
    number of columns7,195
    structural full rank?yes
    structural rank426
    numerical rank 367
    dimension of the numerical null space6,828
    numerical rank / min(size(A))0.8615
    Euclidean norm of A 41.545
    calculated singular value # 3670.71811
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    5.1124e-011
    calculated singular value # 3689.16e-014
    gap in the singular values at the numerical rank:
    singular value # 367 / singular value # 368
    7.8397e+012
    calculated condition number2.588e+017
    condest-2
    nonzeros52,121
    # of blocks from dmperm1
    # strongly connected comp.1
    entries not in dmperm blocks0
    explicit zero entries0
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    typebinary
    structurerectangular
    Cholesky candidate?no
    positive definite?no

    author
    editorC. Meszaros
    date2004
    kindlinear programming problem
    2D/3D problem?no
    SJid446
    UFid1,682

    Additional fieldssize and type
    bfull 426-by-1
    cfull 7195-by-1
    lofull 7195-by-1
    hifull 7195-by-1
    z0full 1-by-1

    Notes:

    http://www.sztaki.hu/~meszaros/public_ftp/lptestset      
    Converted to standard form via Resende and Veiga's mpsrd:
    minimize c'*x, subject to A*x=b and lo <= x <= hi        
    

    Ordering statistics:AMD METIS
    nnz(V) for QR, upper bound nnz(L) for LU1,896,475 2,038,988
    nnz(R) for QR, upper bound nnz(U) for LU68,054 70,140

    Maintained by Leslie Foster, last updated 24-Apr-2009.

    Entries 5 through 14 in the table of matrix properties and the singular
    value plot were created using SJsingular code. The other plots
    and statistics are produced using utilities from the SuiteSparse package.
    Matrix color plot pictures by cspy, a MATLAB function in the CSparse package.