CALL SFT(F,NPTS,NSPEC,AMP,PHI) -- This routine performs a Fourier
 series transform on the set of points F.  FCTR: SF
 
 F - Array of points for which the transform is to be taken, must be
     equally spaced.
 NPTS - Number of points, must be odd.
 NSPEC - Number of harmonic to calculate.
 AMP - Array of RMS amplitudes.
 PHI - Array of phase angles in radians.