Routine svd from Matlab 7.6.0.324 (R2008a) used to calculate the singular values.
| Matrix properties (click for a legend) | |
| number of rows | 244 |
| number of columns | 2,595 |
| structural full rank? | yes |
| structural rank | 244 |
| numerical rank | 243 |
| dimension of the numerical null space | 2,352 |
| numerical rank / min(size(A)) | 0.9959 |
| Euclidean norm of A | 22731 |
| calculated singular value # 243 | 1.4051 |
| numerical rank defined using a tolerance max(size(A))*eps(norm(A)) = | 9.4406e-009 |
| calculated singular value # 244 | 1.7575e-010 |
| gap in the singular values at the numerical rank: singular value # 243 / singular value # 244 | 7.995e+009 |
| calculated condition number | 1.2934e+014 |
| condest | -2 |
| nonzeros | 70,216 |
| # of blocks from dmperm | 1 |
| # strongly connected comp. | 1 |
| entries not in dmperm blocks | 0 |
| explicit zero entries | 0 |
| nonzero pattern symmetry | 0% |
| numeric value symmetry | 0% |
| type | real |
| structure | rectangular |
| Cholesky candidate? | no |
| positive definite? | no |
| author | J. Tomlin |
| editor | D. Gay |
| date | 1989 |
| kind | linear programming problem |
| 2D/3D problem? | no |
| SJid | 358 |
| UFid | 701 |
| Additional fields | size and type |
| b | full 244-by-1 |
| c | full 2595-by-1 |
| lo | full 2595-by-1 |
| hi | full 2595-by-1 |
| z0 | full 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 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
WOOD1P 245 2594 70216 328905 1.4429024116E+00
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
WOOD1P 1059 471 44.48
Added to Netlib on 27 June 1989
| Ordering statistics: | AMD | METIS |
| nnz(V) for QR, upper bound nnz(L) for LU | 248,714 | 463,570 |
| nnz(R) for QR, upper bound nnz(U) for LU | 19,080 | 25,051 |
Maintained by Leslie Foster, last updated 24-Apr-2009.
Entries 5 through 14 in the table of matrix properties and the singular
value plot were created using SJsingular code. The other plots
and statistics are produced using utilities from
the SuiteSparse package.
Matrix color plot pictures by cspy, a MATLAB function in the CSparse package.