Description: Schenk: IBM TJ Watson, Yorktown, nonlinear optimization
|(undirected graph drawing)|
|number of rows||37,595|
|number of columns||37,595|
|structural full rank?||yes|
|# of blocks from dmperm||4|
|# strongly connected comp.||4|
|explicit zero entries||6|
|nonzero pattern symmetry||symmetric|
|numeric value symmetry||symmetric|
|Additional fields||size and type|
Revised Nov 2006; relative eps changes to A, right-hand-side added. Note that this matrix should have been placed in the Schenk_IBMNA/ directory when it was first added in August 2004, but moving it now would disrupt exising users of the collection.
|nnz(chol(P*(A+A'+s*I)*P')) with AMD||2,291,656|
|Cholesky flop count||1.9e+09|
|nnz(L+U), no partial pivoting, with AMD||4,545,717|
|nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD||101,554,464|
|nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD||148,881,383|
Note that all matrix statistics (except nonzero pattern symmetry) exclude the 6 explicit zero entries.
|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.