Description: Gould,Hu,Scott: nearly same pattern as Schenk_IBMNA/c-62, diff. values
|(undirected graph drawing)|
|number of rows||41,731|
|number of columns||41,731|
|structural full rank?||yes|
|# of blocks from dmperm||3|
|# strongly connected comp.||3|
|explicit zero entries||4|
|nonzero pattern symmetry||symmetric|
|numeric value symmetry||symmetric|
|kind||subsequent optimization problem|
|Additional fields||size and type|
next: - first: Schenk_IBMNA/c-62 A version of this matrix was first obtained from Olaf Schenk in October 2003. That version appears in this collection as Schenk_IBMNA/c-62. In August 2004, a new version appeared in the GHS collection, under the same name, and was added here as GHS_indef/c-62ghs. The c-62ghs matrix is the same as the version on Schenk's web site as of Nov 2006, except that the right-hand-side was missing in the version in the UF Sparse Matrix Collection (now included). The two matrices c-62 and c-62ghs are very similar, but not identical.
|nnz(chol(P*(A+A'+s*I)*P')) with AMD||9,819,875|
|Cholesky flop count||1.7e+10|
|nnz(L+U), no partial pivoting, with AMD||19,598,019|
|nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD||125,385,616|
|nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD||173,361,037|
Note that all matrix statistics (except nonzero pattern symmetry) exclude the 4 explicit zero entries.
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.