Calculate multivariate mode indicator function.
MIF = MMIF(F[,CT][,TAM][,'nofp'][,'silent'])
MMIF will compute the multivariate mode indicator functions from the frequency response functions in the supplied imat_fn F. One multivariate MIF will be computed for each reference in F. If requested, MMIF will also compute the force patterns. You will receive NREF force patterns for each reference, where NREF is the number of references.
CT is an optional imat_ctrace that specifies which response coordinates to use in the multivariate MIF calculation. SUB is an optional substructure containing at least .aset and .mass fields. If TAM is supplied, MMIF will use the mass matrix instead of the identity matrix in the calculation. It uses the DOF specified in the TAM.aset field. If TAM is used, MMIF will automatically change sign on FRF with negative response directions.
CT and TAM are mutually exclusive.
If the optional string argument 'nofp' is supplied, MMIF will not calculate force patterns. If the optional string argument 'silent' is supplied, MMIF will suppress all its output.
MIF is an imat_fn output that will have the same attributes as the input F, except that the functions will be a Mode Indicator Function or Force Pattern, and the ordinate data types are unknown. The reference coordinates for the MIFs are set from 1 to the number of reference, and the response coordinates are set to the number of references. The response coordinates of the force patterns correspond to each reference. The reference coordinates correspond to each MIF.
>> [MIF]=mmif(f)
>> [MIF]=mmif(f,ct)
>> [MIF]=mmif(f,ct,’nofp’)
>> [MIF]=mmif(f,TAM)
>> [MIF]=mmif(f,TAM,’nofp’)