fault is 1:length(V(:,1))
       Type        String with 'd' for dynamic flexibility (displacement/force)
                   String with 'v' for mobility (velocity/force) (Default)
                   String with 'a' for accelerance (acceleration/force)
       N           length(f), number of frequency values to compute H on

 Note: For all modes, only one mode shape and pole out of every
 complex conjugate pair should be included in p and V. The complex
 conjugate is produced by this function. p and V must 