• UF Sparse Matrix Collection
  • Matrix group: Boeing
  • Click here for a description of the Boeing group.
  • Click here for a list of all matrices
  • Click here for a list of all matrix groups


  • Matrix: Boeing/ct20stif
  • Description: CT20 ENGINE BLOCK -- STIFFNESS MATRIX
  • download as a MATLAB mat-file, file size: 17 MB. Use UFget(356) or UFget('Boeing/ct20stif') in MATLAB.
  • download in Matrix Market format
  • download in Rutherford/Boeing format

    Boeing/ct20stif

    Boeing/ct20stif graph

    Matrix properties
    number of rows52,329
    number of columns52,329
    nonzeros2,600,295
    structural full rank?yes
    structural rank52,329
    # of blocks from dmperm1
    # strongly connected comp.1
    entries not in dmperm blocks0
    explicit zero entries98,168
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typereal
    structuresymmetric
    Cholesky candidate?yes
    positive definite?yes

    authorR. Grimes
    editorT. Davis
    date1995
    kindstructural problem
    2D/3D problem?yes

    Ordering statistics:AMD METIS
    nnz(chol(P*(A+A'+s*I)*P'))10,729,657 9,637,259
    Cholesky flop count7.1e+09 4.5e+09
    nnz(L+U), no partial pivoting21,406,985 19,222,189
    nnz(V) for QR, upper bound nnz(L) for LU26,993,567 18,758,245
    nnz(R) for QR, upper bound nnz(U) for LU52,637,780 37,457,116

    Note that all matrix statistics (except nonzero pattern symmetry) exclude the 98168 explicit zero entries.

    Maintained by Tim Davis, last updated 04-May-2008.
    Matrix pictures by cspy, a MATLAB function in the CSparse package.
    Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.