• SJSU Singular Matrix Database
• Matrix group: Mancktelow
• Click here for a description of the Mancktelow group.
• Click here for a list of all matrices
• Click here for a list of all matrix groups

• Matrix: Mancktelow/viscorocks
• Description: FEM viscoelastic behavior of rocks, Neil Mancktelow, ETH-Zentrum
• download as a MATLAB mat-file, file size: 6 MB. Use SJget(527) or SJget('Mancktelow/viscorocks') in MATLAB.
• download in Matrix Market format, file size: 11 MB.
• download in Rutherford/Boeing format, file size: 10 MB.

A singular value of A is guaranteed1 to be in the interval pictured by the blue bars around each of the calculated singular values.

Routine svds_err, version 1.0, used with Matlab 7.6.0.324 (R2008a) to calculate the 6 largest singular values and associated error bounds.
Routine spnrank, version 1.0 with opts.tol_eigs = 1e-010, used with Matlab 7.6.0.324 (R2008a) to calculate singular values 37750 to 37755 and associated error bounds.  Matrix properties (click for a legend) number of rows 37,762 number of columns 37,762 structural full rank? yes structural rank 37,762 numerical rank 37,752 dimension of the numerical null space 10 numerical rank / min(size(A)) 0.99974 Euclidean norm of A 7.4163e+007 calculated singular value # 37752 0.00064267 numerical rank defined using a tolerance max(size(A))*eps(norm(A)) = 0.0005627 calculated singular value # 37753 0.0005202 gap in the singular values at the numerical rank: singular value # 37752 / singular value # 37753 1.2354 calculated condition number -2 condest 3.2464e+012 nonzeros 1,133,641 # of blocks from dmperm 773 # strongly connected comp. 773 entries not in dmperm blocks 0 explicit zero entries 28,603 nonzero pattern symmetry symmetric numeric value symmetry 28% type real structure unsymmetric Cholesky candidate? no positive definite? no

 author N. Mancktelow editor T. Davis date 2007 kind materials problem 2D/3D problem? yes SJid 527 UFid 1,879

 Ordering statistics: AMD METIS DMPERM+ nnz(chol(P*(A+A'+s*I)*P')) 2,711,148 3,188,233 2,711,148 Cholesky flop count 3.3e+008 4.4e+008 3.3e+008 nnz(L+U), no partial pivoting 5,384,534 6,338,704 5,384,534 nnz(V) for QR, upper bound nnz(L) for LU 6,061,883 5,235,031 5,273,603 nnz(R) for QR, upper bound nnz(U) for LU 14,916,823 11,979,793 12,097,349

Note that all matrix statistics (except nonzero pattern symmetry) exclude the 28603 explicit zero entries.

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.