nmif


Purpose

Compute normal mode indicator function.

Syntax

MIF = NMIF(F[,'real'][,'imag'][,CT])

Description

NMIF will compute the normal mode indicator function from the frequency response functions in the supplied imat_fn FN. One mode indicator function will be computed for each reference in F. If there is more than one reference, a NMIF will also be computed that contains all of the FRF for all references.

If the FRF ordinate numerator data type is velocity, the imaginary portion of the FRF will be used in the numerator of the NMIF equation. For all other data types the real portion of the FRF will be used. It is possible to override this behavior by passing in the string 'real' or 'imag'.

CT is an optional imat_ctrace containing response DOF to use in the calculation. They must all be present for each reference, otherwise an error will occur.

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 and the ordinate data types are unknown. The reference coordinates will be set to the reference coordinate used to calculate the MIF, and the response coordinate is set to '1NMIF'.

Examples

>> MIF=nmif(f)
>> MIF=nmif(f,ct)

See Also

mmif, psmif, cmif