• SJSU Singular Matrix Database
• Matrix group: HB

• Matrix: HB/plsk1919
• Description: PLATZMAN SKEW-SYMMETRIC FINITE DIFFERENCE THREE OCEAN MODEL
• download as a MATLAB mat-file, file size: 88 KB. Use SJget(208) or SJget('HB/plsk1919') in MATLAB.

Routine svd from Matlab 7.6.0.324 (R2008a) used to calculate the singular values.

 Matrix properties (click for a legend) number of rows 1,919 number of columns 1,919 structural full rank? yes structural rank 1,919 numerical rank 1,918 dimension of the numerical null space 1 numerical rank / min(size(A)) 0.99948 Euclidean norm of A 1.7093 calculated singular value # 1918 3.2994e-007 numerical rank defined using a tolerance max(size(A))*eps(norm(A)) = 4.261e-013 calculated singular value # 1919 1.2912e-017 gap in the singular values at the numerical rank: singular value # 1918 / singular value # 1919 2.5553e+010 calculated condition number 1.3238e+017 condest 4.4526e+018 nonzeros 9,662 # of blocks from dmperm 11 # strongly connected comp. 1 entries not in dmperm blocks 24 explicit zero entries 0 nonzero pattern symmetry symmetric numeric value symmetry 0% type real structure skew-symmetric Cholesky candidate? no positive definite? no

 author J. Lewis editor I. Duff, R. Grimes, J. Lewis date 1975 kind 2D/3D problem 2D/3D problem? yes SJid 208 UFid 230

 Ordering statistics: AMD METIS DMPERM+ nnz(chol(P*(A+A'+s*I)*P')) 16,733 19,881 41,259 Cholesky flop count 2.0e+005 3.1e+005 1.2e+006 nnz(L+U), no partial pivoting 31,547 37,843 80,623 nnz(V) for QR, upper bound nnz(L) for LU 31,694 38,779 33,581 nnz(R) for QR, upper bound nnz(U) for LU 66,710 77,074 68,647

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.