Matrix: LPnetlib/lp_truss

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

LPnetlib/lp_truss graph
(bipartite graph drawing)


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  • download as a MATLAB mat-file, file size: 39 KB. Use UFget(698) or UFget('LPnetlib/lp_truss') in MATLAB.
  • download in Matrix Market format, file size: 88 KB.
  • download in Rutherford/Boeing format, file size: 46 KB.

    Matrix properties
    number of rows1,000
    number of columns8,806
    structural full rank?yes
    structural rank1,000
    # of blocks from dmperm1
    # strongly connected comp.1
    explicit zero entries0
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    Cholesky candidate?no
    positive definite?no

    authorM. Ferris
    editorD. Gay
    kindlinear programming problem
    2D/3D problem?no

    Additional fieldssize and type
    bfull 1000-by-1
    cfull 8806-by-1
    lofull 8806-by-1
    hifull 8806-by-1
    z0full 1-by-1


    A Netlib LP problem, from a generator in lp/data.  For more information       
    send email to with the message:                               
    	 send index from lp                                                          
    	 send readme from lp/data                                                    
    This copy of TRUSS was created by the TRUSS generator program,                
    on an Sun UltraSparc, on May 15, 1997.                                        
    The following are relevant excerpts from lp/data/readme (by David M. Gay):    
    The column and nonzero counts in the PROBLEM SUMMARY TABLE below exclude      
    slack and surplus columns and the right-hand side vector, but include         
    the cost row.  We have omitted other free rows and all but the first          
    right-hand side vector, as noted below.  The byte count is for the            
    MPS compressed file; it includes a newline character at the end of each       
    line.  These files start with a blank initial line intended to prevent        
    mail programs from discarding any of the data.  The BR column indicates       
    whether a problem has bounds or ranges:  B stands for "has bounds", R         
    for "has ranges".                                                             
    The optimal value is from MINOS version 5.3 (of Sept. 1988)                   
    running on a VAX with default options.                                        
                           PROBLEM SUMMARY TABLE                                  
    Name       Rows   Cols   Nonzeros    Bytes  BR      Optimal Value             
    TRUSS      1001   8806    36642 (see NOTES)       4.5881584719E+05            
    Source:  At the request of Olvi Mangasarian, Rudy Setiono supplied the        
    generator and description (both written by Michael Ferris) and data for TRUSS.
    Requesting TRUSS will get you a bundle of Fortran source and data for         
    generating an MPS file for TRUSS, a problem of minimizing the weight          
    of a certain structure.  The bundle also includes a description of the        
    Added to Netlib on  26 Feb. 1990                                              

    Ordering statistics:result
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD1,647,142
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD51,088

    SVD-based statistics:
    null space dimension0
    full numerical rank?yes

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

    LPnetlib/lp_truss 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.