Description: Netlib LP problem maros_r7: minimize c'*x, where Ax=b, lo<=x<=hi
|(bipartite graph drawing)|
|number of rows||3,136|
|number of columns||9,408|
|structural full rank?||yes|
|# of blocks from dmperm||1|
|# strongly connected comp.||1|
|explicit zero entries||0|
|nonzero pattern symmetry||0%|
|numeric value symmetry||0%|
|kind||linear programming problem|
|Additional fields||size and type|
A Netlib LP problem, in lp/data. For more information send email to email@example.com 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 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 MAROS-R7 3137 9408 151120 4812587 1.4971851665E+06 From Istvan Maros. Concerning the problems he submitted, Istvan Maros says that MAROS-R7 is "an interesting real-life LP problem which appeared hard to some solvers." It "is an image restoration problem done via a goal programming approach. It is structured, namely, its first section is a band matrix with the dominating number of nonzeros, while the second section is also a band matrix with bandwidth equals 2 and coefficients +1, -1. The problem is a representative of a family of problems in which the number of rows and the bandwidth of the first section can vary. This one is a medium size problem from the family. MAROS-R7 became available in cooperation with Roni Levkovitz and Carison Tong." Added to Netlib on 17 Jan. 1994
|nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD||9,862,844|
|nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD||853,785|
|null space dimension||0|
|full numerical rank?||yes|
|singular values (MAT file):||click here|
|SVD method used:||s = svd (full (A)) ;|
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.