Matrix: HB/orsirr_1
Description: U OIL RESERVOIR SIMULATION MATRIX FOR 21X21X 5 IRREGULAR GRID
(undirected graph drawing) |
Matrix properties | |
number of rows | 1,030 |
number of columns | 1,030 |
nonzeros | 6,858 |
structural full rank? | yes |
structural rank | 1,030 |
# of blocks from dmperm | 1 |
# strongly connected comp. | 1 |
explicit zero entries | 0 |
nonzero pattern symmetry | symmetric |
numeric value symmetry | 41% |
type | real |
structure | unsymmetric |
Cholesky candidate? | no |
positive definite? | no |
author | R. Grimes |
editor | I. Duff, R. Grimes, J. Lewis |
date | 1984 |
kind | computational fluid dynamics problem |
2D/3D problem? | yes |
Ordering statistics: | result |
nnz(chol(P*(A+A'+s*I)*P')) with AMD | 25,702 |
Cholesky flop count | 1.2e+06 |
nnz(L+U), no partial pivoting, with AMD | 50,374 |
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD | 52,433 |
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD | 93,121 |
SVD-based statistics: | |
norm(A) | 458081 |
min(svd(A)) | 5.93809 |
cond(A) | 77142.8 |
rank(A) | 1,030 |
sprank(A)-rank(A) | 0 |
null space dimension | 0 |
full numerical rank? | yes |
singular values (MAT file): | click here |
SVD method used: | s = svd (full (A)) ; |
status: | ok |
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.