pro polyfit
  green = GETCOLOR('green', 100)
  red = GETCOLOR('red', 100)


  enkey="B21"
  fn = '../products/detcnts.'+enkey+'.ALL.resid.fits'
  
  table  = readfits(fn, header, EXTEN_NO=1, /SILENT)
  
  
  ;;tstart = TBGET( header, table, 'TSTART', /NOSCALE)
  ;;tstop  = TBGET( header, table, 'TSTOP', /NOSCALE)
  rev   = TBGET( header, table, 'REV', /NOSCALE)
  data   = TBGET( header, table, 'RESID', /NOSCALE)
  time = LINDGEN(N_ELEMENTS(data))


  rev_min=min(rev)
  rev_max=max(rev)

  plot_x=[]
  plot_y=[]
  
  for r=rev_min, rev_max do begin
     index = where(rev eq r, count)
     if(count lt 10) then continue
     mn = AVG(data(index))
     push,plot_x,r
     push,plot_y,mn
     print,r,count,mn
  endfor
  
  plot,plot_x,plot_y                ;, yrange=[-0.0001,0.0001]

  return

  
  ;;COEFF = ROBUST_LINEFIT(time, rate, YFIT, SIG, COEF_SIG)
  COEFF = ROBUST_POLY_FIT(time,data,7,YFIT,SIG, /DOUBLE)

  print,SIG
  print,COEFF
  
  ;mean_polyfit=AVG(YFIT)
  ;print,'mean fit',mean_polyfit
  ;print,'resid',SIG/mean_polyfit*100

  poly = coeff;/mean_polyfit
  ;;save,FILENAME = enkey+'_poly.sav', poly, mean_polyfit
  
  scale=1.2
  ;;yfit0 = (poly[0] + poly[1]*time + poly[2]*time^2 + poly[3]*time^3)*scale
  
  plot,time,data;, yrange=[-0.0001,0.0001]
  oplot,time,YFIT,color=green
  ;;oplot,time,YFIT0,color=red
end