{HEAD ~ The method} may further include filtering the Fourier transformed data to retain a subset of the Fourier coefficients at {TAIL ~ each} of the locations 
{ HEAD ~ The method } may further include filtering the Fourier transformed data to retain a subset of the Fourier coefficients at { TAIL ~ each } of the locations
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH