Matrix: LPnetlib/lp_standgub

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

LPnetlib/lp_standgub graph
(bipartite graph drawing)


LPnetlib/lp_standgub dmperm of LPnetlib/lp_standgub
scc of LPnetlib/lp_standgub

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  • download as a MATLAB mat-file, file size: 8 KB. Use UFget(693) or UFget('LPnetlib/lp_standgub') in MATLAB.
  • download in Matrix Market format, file size: 14 KB.
  • download in Rutherford/Boeing format, file size: 10 KB.

    Matrix properties
    number of rows361
    number of columns1,383
    nonzeros3,338
    structural full rank?no
    structural rank360
    # of blocks from dmperm2
    # strongly connected comp.4
    explicit zero entries1
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    typereal
    structurerectangular
    Cholesky candidate?no
    positive definite?no

    authorR. Fourer
    editorR. Fourer
    date1989
    kindlinear programming problem
    2D/3D problem?no

    Additional fieldssize and type
    bfull 361-by-1
    cfull 1383-by-1
    lofull 1383-by-1
    hifull 1383-by-1
    z0full 1-by-1

    Notes:

    A Netlib LP problem, in lp/data.  For more information                    
    send email to netlib@ornl.gov with the message:                           
                                                                              
    	 send index from lp                                                      
    	 send readme from lp/data                                                
                                                                              
    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 BOUND-TYPE TABLE below shows the bound types       
    present in those problems that have bounds.                               
                                                                              
    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         
    STANDGUB    362   1184     3147      27836  B     (see NOTES)             
                                                                              
            BOUND-TYPE TABLE                                                  
    STANDGUB   UP    FX                                                       
                                                                              
    Supplied by Bob Fourer.                                                   
                                                                              
    STANDGUB includes GUB markers; with these lines removed (lines in         
    the expanded MPS file that contain primes, i.e., that mention the rows    
    'EGROUP' and 'ENDX'), STANDGUB becomes the same as problem STANDATA;      
    MINOS does not understand the GUB markers, so we cannot report an         
    optimal value from MINOS for STANDGUB.  STANDMPS amounts to STANDGUB      
    with the GUB constraints as explicit constraints.                         
                                                                              
    Source: consulting.                                                       
    

    Ordering statistics:result
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD40,450
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD3,386

    Note that all matrix statistics (except nonzero pattern symmetry) exclude the 1 explicit zero entries.

    SVD-based statistics:
    norm(A)671.315
    min(svd(A))7.02998e-17
    cond(A)9.54932e+18
    rank(A)360
    sprank(A)-rank(A)0
    null space dimension1
    full numerical rank?no
    singular value gap4.24687e+15

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

    LPnetlib/lp_standgub 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.