Group LPnetlib

Group Description
NETLIB Linear Programming problems, www.netlib.org.

matrices/LPnetlib/README.  Tim Davis, May 15, 1997. (davis :at the domain:
cise.ufl.edu)

The files in this directory are a translation of the linear programming
problems in Netlib.  You can obtain more information about the Netlib LP
problems by sending email to netlib :at the domain:
ornl.gov with the message
"send index from lp".


++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
NOTICE!  The Netlib LP problems, in MPS format, should be considered the
"canonical" problems.  If you find any problems with different optimal
objectives than what is reported in Netlib, then please let me know.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

The Netlib LP problems are in MPS or compressed MPS format.  Any compressed
MPS files were uncompressed using emps.c in the Netlib lp/data directory.
The MPS files were then converted to the KAR format using the mpsrd program
by M.G.C. Resende and G. Veiga.  The mpsrd program does not process RANGES,
so five problems (boeing1, boeing2, forplan, nesm, and seba) do not appear
here.  The KAR format is written out by mpsrd as follows:

c     name   - problem name (same as mps name card)
      write(out,'(a8)') name
c     m      - number or rows (input)
c     n      - number of columns (input)
      write(out,*) m,n
c     ia     - pointers to the begining of storage of column
      write(out,*) (ia(i),i=1,n+1)
c     ja     - row indices for each non zero entry (input)
      write(out,*) (ja(i),i=1,ia(n+1)-1)
c     a      - non zero entries (input)
      write(out,*) (a(i),i=1,ia(n+1)-1)
c     b      - right hand side (input)
      write(out,*) (b(i),i=1,m)
c     c      - objective vector (minimize)
      write(out,*) (c(i),i=1,n)
c     z0     - initial fixed value for objective
      write(out,*) z0
c     lobnd  - lower bounds on variables
      write(out,*) (lobnd(i),i=1,n)
c     upbnd  - upper bounds on variables
      write(out,*) (upbnd(i),i=1,n)

Mpsrd converts the MPS problem into a single form:

	minimize c'*x, subject to Ax=b and l<=x<=u.
	(and given an initial value of the objective, z0).

Next, the KAR formatted version of the LP problem was converted into
two formats by the readkar.f program, written by Tim Davis.  It generates
a single Matlab script, such as lp_afiro.m for the AFIRO problem.
For infeasible (lp/infeas) problems, the prefix is lpi_ (lpi_galenet.m for
the problem GALENET, for example).  This prefix was chosen so that you
are sure to notice that the problem is infeasible, and also because there
are two versions of the same problem in Netlib (GREENBEA), one feasible
and the other not.



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The *.clu files contain the c, l, and u vectors,
and the scalar z0, for the LP problems held in
RRA format in the LPnetlib directory.  The dense vectors
appear in order: c, l, u, and then z0.  One entry is held
on each line. 

The RRA files contain A and b, in Harwell/Boeing format.

The LP problems are all of the form

	minimize c'*x, subject to Ax=b and l<=x<=u
	and where z0 is the initial value of the
	objective.
Displaying collection matrices 1 - 20 of 138 in total
Id Name Group Rows Cols Nonzeros Kind Date Download File
594 lp_25fv47 LPnetlib 821 1,876 10,705 Linear Programming Problem 1978 MATLAB Rutherford Boeing Matrix Market
595 lp_80bau3b LPnetlib 2,262 12,061 23,264 Linear Programming Problem MATLAB Rutherford Boeing Matrix Market
596 lp_adlittle LPnetlib 56 138 424 Linear Programming Problem MATLAB Rutherford Boeing Matrix Market
597 lp_afiro LPnetlib 27 51 102 Linear Programming Problem MATLAB Rutherford Boeing Matrix Market
598 lp_agg LPnetlib 488 615 2,862 Linear Programming Problem 1988 MATLAB Rutherford Boeing Matrix Market
599 lp_agg2 LPnetlib 516 758 4,740 Linear Programming Problem 1988 MATLAB Rutherford Boeing Matrix Market
600 lp_agg3 LPnetlib 516 758 4,756 Linear Programming Problem 1988 MATLAB Rutherford Boeing Matrix Market
601 lp_bandm LPnetlib 305 472 2,494 Linear Programming Problem MATLAB Rutherford Boeing Matrix Market
602 lp_beaconfd LPnetlib 173 295 3,408 Linear Programming Problem MATLAB Rutherford Boeing Matrix Market
603 lp_blend LPnetlib 74 114 522 Linear Programming Problem 1989 MATLAB Rutherford Boeing Matrix Market
604 lp_bnl1 LPnetlib 643 1,586 5,532 Linear Programming Problem 1989 MATLAB Rutherford Boeing Matrix Market
605 lp_bnl2 LPnetlib 2,324 4,486 14,996 Linear Programming Problem 1989 MATLAB Rutherford Boeing Matrix Market
606 lp_bore3d LPnetlib 233 334 1,448 Linear Programming Problem MATLAB Rutherford Boeing Matrix Market
607 lp_brandy LPnetlib 220 303 2,202 Linear Programming Problem MATLAB Rutherford Boeing Matrix Market
608 lp_capri LPnetlib 271 482 1,896 Linear Programming Problem MATLAB Rutherford Boeing Matrix Market
609 lp_cre_a LPnetlib 3,516 7,248 18,168 Linear Programming Problem 1990 MATLAB Rutherford Boeing Matrix Market
610 lp_cre_b LPnetlib 9,648 77,137 260,785 Linear Programming Problem 1990 MATLAB Rutherford Boeing Matrix Market
611 lp_cre_c LPnetlib 3,068 6,411 15,977 Linear Programming Problem 1990 MATLAB Rutherford Boeing Matrix Market
612 lp_cre_d LPnetlib 8,926 73,948 246,614 Linear Programming Problem 1990 MATLAB Rutherford Boeing Matrix Market
613 lp_cycle LPnetlib 1,903 3,371 21,234 Linear Programming Problem 1989 MATLAB Rutherford Boeing Matrix Market