**Matrix: HB/fs_680_2**

Description: UNSYMMETRIC FACSIMILE CONVERGENCE MATRIX

(bipartite graph drawing) | (graph drawing of A+A') |

Matrix properties | |

number of rows | 680 |

number of columns | 680 |

nonzeros | 2,424 |

structural full rank? | yes |

structural rank | 680 |

# of blocks from dmperm | 446 |

# strongly connected comp. | 446 |

explicit zero entries | 222 |

nonzero pattern symmetry | 51% |

numeric value symmetry | 0% |

type | real |

structure | unsymmetric |

Cholesky candidate? | no |

positive definite? | no |

author | A. Curtis |

editor | I. Duff, R. Grimes, J. Lewis |

date | 1983 |

kind | subsequent 2D/3D problem |

2D/3D problem? | yes |

Notes:

next: HB/fs_680_3 first: HB/fs_680_1

Ordering statistics: | result |

nnz(chol(P*(A+A'+s*I)*P')) with AMD | 2,620 |

Cholesky flop count | 1.4e+04 |

nnz(L+U), no partial pivoting, with AMD | 4,560 |

nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD | 2,056 |

nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD | 3,971 |

*Note that all matrix statistics (except nonzero pattern symmetry) exclude the 222 explicit zero entries.
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SVD-based statistics: | |

norm(A) | 7.19085e+13 |

min(svd(A)) | 4.899e+08 |

cond(A) | 146782 |

rank(A) | 680 |

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 |

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*For a description of the statistics displayed above,
click here.
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*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.
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