LPnetlib/lp_tuff

Netlib LP problem tuff: minimize c'*x, where Ax=b, lo<=x<=hi
Name lp_tuff
Group LPnetlib
Matrix ID 699
Num Rows 333
Num Cols 628
Nonzeros 4,561
Pattern Entries 4,561
Kind Linear Programming Problem
Symmetric No
Date 1989
Author J. Tomlin
Editor D. Gay
Structural Rank 302
Structural Rank Full false
Num Dmperm Blocks 12
Strongly Connect Components 41
Num Explicit Zeros 0
Pattern Symmetry 0%
Numeric Symmetry 0%
Cholesky Candidate no
Positive Definite no
Type real
SVD Statistics
Matrix Norm 1.000288e+04
Minimum Singular Value 3.151872e-17
Condition Number 3.173631e+20
Rank 302
sprank(A)-rank(A) 0
Null Space Dimension 31
Full Numerical Rank? no
Download Singular Values MATLAB
Download MATLAB Rutherford Boeing Matrix Market
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         
TUFF        334    587     4523      29439  B     2.9214776509E-01        
                                                                          
        BOUND-TYPE TABLE                                                  
TUFF       UP LO FX FR                                                    
                                                                          
Empty RHS section.                                                        
                                                                          
From John Tomlin.                                                         
On the problems supplied by John Tomlin, MINOS 5.3 reports that about     
10% to 57% of its steps are degenerate:                                   
     Name     Steps  Degen  Percent                                       
     TUFF       745    345   46.31                                        
                                                                          
Added to Netlib on  27 June 1989.