PARAM, MFILTER

Bulk Data Entry Defines a threshold for the mode tracking matrix to check eigenvector correspondence.

Parameter Values Description
MFILTER <0.0 ≤ real number ≤ 1.0>
Defaults:
  • If this parameter is included in the input file, but, no value is provided, then running the program will result in an error. In such cases a real value between 0.0 and 1.0 must be specified.
  • If this parameter is not included in the input file, then:
    • The value of filtering threshold (MFILTER) is equal to 0.7 if PARAM, TRAKMETH is set to 0 or 1.
    • The value of the filtering threshold (MFILTER) is equal to 0.5 if PARAM, TRAKMETH is set to 2.
 This parameter defines a threshold for the mode tracking matrix to check eigenvector correspondence. This can also be controlled via the MODTRAK Bulk Data Entry.

If an entry of the mode tracking matrix is greater than the specified threshold, the eigenvectors of previous and current iterations (corresponding to the row number and column number of the entry) are assumed to have correspondence.

If PARAM, TRAKMETH or the TRAKMETH field on the MODTRAK Bulk Data Entry is set to 0 , the mass matrix based cross-orthogonality criterion (CORC) is used to check for eigenvector correspondence, and the filtering threshold (MFLITER) is set to 0.7.

If PARAM, TRAKMETH or the TRAKMETH field on the MODTRAK Bulk Data Entry is set to 1, the modal assurance criterion square root (MACSR) is used, and the filtering threshold (MFILTER) is set to 0.7.

If PARAM, TRAKMETH or the TRAKMETH field on the MODTRAK Bulk Data Entry is set to 2, the modal assurance criterion (MAC) is used and the filtering threshold (MFILTER) is set to 0.5.