Matrix: LPnetlib/lpi_gran

Description: Netlib LP problem gran: minimize c'*x, where Ax=b, lo<=x<=hi

LPnetlib/lpi_gran graph
(bipartite graph drawing)


LPnetlib/lpi_gran dmperm of LPnetlib/lpi_gran
scc of LPnetlib/lpi_gran

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  • Matrix group: LPnetlib
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  • download as a MATLAB mat-file, file size: 55 KB. Use UFget(717) or UFget('LPnetlib/lpi_gran') in MATLAB.
  • download in Matrix Market format, file size: 91 KB.
  • download in Rutherford/Boeing format, file size: 54 KB.

    Matrix properties
    number of rows2,658
    number of columns2,525
    nonzeros20,111
    structural full rank?no
    structural rank2,311
    # of blocks from dmperm1,267
    # strongly connected comp.1,243
    explicit zero entries0
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    typereal
    structurerectangular
    Cholesky candidate?no
    positive definite?no

    authorR. Main
    editorJ. Chinneck
    date1993
    kindlinear programming problem
    2D/3D problem?no

    Additional fieldssize and type
    bfull 2658-by-1
    cfull 2525-by-1
    lofull 2525-by-1
    hifull 2525-by-1
    z0full 1-by-1

    Notes:

    An infeasible Netlib LP problem, in lp/infeas.  For more information        
    send email to netlib@ornl.gov with the message:                             
                                                                                
    	send index from lp                                                         
    	send readme from lp/infeas                                                 
                                                                                
    The lp/infeas directory contains infeasible linear programming test problems
    collected by John W. Chinneck, Carleton Univ, Ontario Canada.  The following
    are relevant excerpts from lp/infeas/readme (by John W. Chinneck):          
                                                                                
    PROBLEM DESCRIPTION                                                         
    -------------------                                                         
                                                                                
    GOSH, GRAN, PANG:  these very large, large, and medium size models,         
    respectively, problems arose from British Petroleum operations models.      
    Contributor:  Roger Main, BP Oil.                                           
                                                                                
    Name       Rows   Cols   Nonzeros Bounds      Notes                         
    gran       2569   2520    20151   B    FX                                   
                                                                                
    Added to Netlib on Sept. 19, 1993                                           
                                                                                
    

    Ordering statistics:result
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD206,097
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD190,918

    SVD-based statistics:
    norm(A)2079.02
    min(svd(A))1.79119e-17
    cond(A)1.16069e+20
    rank(A)1,938
    sprank(A)-rank(A)373
    null space dimension587
    full numerical rank?no
    singular value gap131.675

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

    LPnetlib/lpi_gran 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.