pro calcspec,fluxarray,spectra,duration,period,sph,nfft,start,missing
;routine to calculate spectra

;determine nchannels, ncols and nrows
arrsize   = size(spectra)
ncols     = arrsize(1)
nrows     = arrsize(2)

fluxpts   = size(fluxarray)
fluxpts   = fluxpts(2)
help,fluxarray
;generate fft times (still using decimal hours):
times = findgen(ncols)
times = start + (duration/ncols)/2 + times*(duration/ncols)

   for j=0,ncols-1 do begin
      ;make sure the data is contained in fluxarray (away from end of file):
      first_time = times(j) - (nfft/2.0)*period/sph
      last_time  = times(j) + (nfft/2.0)*period/sph
      check      = first_time gt fluxarray(0,0) and last_time lt $
         fluxarray(0,fluxpts-1)

      if check then begin ;go ahead and grab the data
         first_data = where(fluxarray(0,*) gt times(j))
         grab = [fluxarray(1,first_data(0)-nfft/2:first_data(0)-1+nfft/2)]
         grab = reform(grab)

         if n_elements(grab ne nfft) then begin
            print,'BIG ERROR!! (in getspec)'
            STOP
         endif
         spectrum       = alog(abs(fft(hanning(nfft)*(grab),-1)))  ;deriv(grab)
         spectrum(0)    = missing
         spectrum(1)    = missing
         spectra(j,*) = spectrum(0:nrows-1)
      endif else begin
         spectra(j,*) = missing ;make this white in color
      endelse
;if j eq 0 and start gt 36. then stop
   endfor

;=========================================================================
;Depress 60 Hz noise by force (including its harmonics, 120 Hz, 180 Hz)

;hzperbin = 1/ (nfft * period)
;
;bin        = fix(60/hzperbin)
;
;dead_bin1   = bin
;dead_bin2   = bin - 1
;dead_bin3   = bin + 1
;dead_bin4   = bin * 2
;dead_bin5   = bin * 2 - 1
;dead_bin6   = bin * 2 + 1
;;dead_bin7   = bin * 3
;dead_bin8   = bin * 3 + 2
;dead_bin9   = bin * 3 + 3
;
;spectra(*,dead_bin1) = 0
;spectra(*,dead_bin2) = 0
;spectra(*,dead_bin3) = 0
;spectra(*,dead_bin4) = 0
;spectra(*,dead_bin5) = 0
;spectra(*,dead_bin6) = 0
;;spectra(*,dead_bin7) = 0
;spectra(*,dead_bin8) = 0
;spectra(*,dead_bin9) = 0

;spectra(*,dead_bin1) = min(spectra)
;spectra(*,dead_bin2) = min(spectra)
;spectra(*,dead_bin3) = min(spectra)
;spectra(*,dead_bin4) = min(spectra)
;spectra(*,dead_bin5) = min(spectra)
;spectra(*,dead_bin6) = min(spectra)
;spectra(*,dead_bin7) = min(spectra)
;spectra(*,dead_bin8) = min(spectra)
;spectra(*,dead_bin9) = min(spectra)

;=========================================================================
;Depress DC component
;spectra(*,0) = 0
;spectra(*,1) = 0

;=========================================================================
;Enhance spectra level
;for kk = 0, ncols-1 do begin
;    for ll = 0, nrows-1 do begin
;       if spectra(kk,ll) LE 2 then begin
;           spectra(kk,ll) = min(spectra)
;       endif else begin
;           spectra(kk,ll) = spectra(kk,ll) * 0.5
;       endelse
;    endfor
;endfor



return
end