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			       SF

      SADFIT is a module which can fit a function to a row of a SAD file.
 The functions presently supported are, a power law, a polynomial, and a 
 series of modeled absorption and/or emission lines with continuum.  Nonlinear
 weighted least squares is used for the solutions.

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 Enter an option:                              21-APR-1992 11:45:28.47
 OPTION=SF
 Enter the filename:  (<CR> for default)
 FILE=SPECTRUM2
 There is one map in the file
 Reading from the file
    1 rows of   60 pixels in R4 format
 Enter the type of fit:
      I = Power law plus constant
      P = Polynomial
      S = Line profiles and continuum for spectral data (default)
  
 CHOICE=
 S     
 Enter the weight scheme:
      E = Equal weights
      R = Weights contained in a row
      S = Weights based on signal-to-noise ratio (default)
  
 WEIGHT_SCHEME=
 S
 Enter the readout noise in electrons and the gain in electrons per ADU:
 (defaults = 10.0 10.0)
 NOISE_PARAMETERS=
   10.0000    
   10.0000    
  
 After the plot is drawn, press C to turn on the cursor.  Then position the
 cursor at the left end of the continuum to be fit and press the <CR>.  For
 each line to be fit, position the cursor at the left side of the line
 (imagined to be unblended) at half amplitude, the peak or bottom of the
 line for an emission or absorption line, respectively, and the imagined
 continuum level in the center of the line.  Press the <CR> at each
 location.  Next, position the cursor at the right end of the 
 continuum to be fit and press the <CR>.  Mistakes can be voided by pressing
 the - key.  Press Q to turn off the cursor and <CR> to proceede.
  
 Press the <CR> when through reading these instructions
 THROUGH=
 T
 Enter the plot devices:
      G  = Graphics terminal (VT100/Retrographics and Visual 550, default)
      G1  = Graphics terminal (GraphOn)
      G2  = Graphics terminal (Codonics)
      G3  = Graphics terminal (Micro-term, Versaterm)
      F   = File
      T   = Tektronix 4662 flat bed plotter (1200 baud)
  
 DEVICES=
 G                             
    4001.51        920.798    	These are the coordinates of each position
    4005.47        812.880    	at which the <CR> was pressed.
    4006.73        715.519    
    4006.73        913.173    
    4010.19        844.551    
    4011.19        765.959    
    4011.19        924.317    
    4012.45        780.622    
    4013.30        616.399    
    4013.30        924.317    
    4017.61        917.865    
   3 lines were chosen to be fit between the limits of
  4000.45     and  4016.05    .
   53 data points will be used in the nonlinear least squares fit
 Enter the degree of the polynomial which will be fit to the continuum:
 (default = 3)
 DEGREE=
          3
              Please wait for the solution
 Mean error for an observation of average weight = 
       9.22081       +-       1.03092    
 The polynomial solution for the continuum is
 DEGREE     COEFFICIENT      MEAN ERROR
  0         0.41083E+07      0.95548E+08
  1         -3169.4           71508.    
  2         0.81437           17.840    
  3        -0.69684E-04      0.14836E-02
 Line Number   1
      Optical Depth = 0.243063     +- 0.775325E-02
      Sigma         = 0.811531     +- 0.329358E-01
      Position      =  4006.56     +- 0.253076E-01
 Line Number   2
      Optical Depth = 0.179165     +- 0.811902E-02
      Sigma         = 0.747693     +- 0.579495E-01
      Position      =  4011.16     +- 0.572024E-01
 Line Number   3
      Optical Depth = 0.379496     +- 0.877719E-02
      Sigma         = 0.779997     +- 0.303247E-01
      Position      =  4013.45     +- 0.289311E-01
 Do you wish to plot the residuals?  (default = Y)
 PLOT_RESIDUALS=
 T
 Enter the plot devices:
      G  = Graphics terminal (VT100/Retrographics and Visual 550, default)
      G1  = Graphics terminal (GraphOn)
      G2  = Graphics terminal (Codonics)
      G3  = Graphics terminal (Micro-term, Versaterm)
      F   = File
      T   = Tektronix 4662 flat bed plotter (1200 baud)
  
 DEVICES=
 G                             
 Do you wish to plot the data and function?  (default = Y)
 PLOT=
 T
 Enter the plot devices:
      G  = Graphics terminal (VT100/Retrographics and Visual 550, default)
      G1  = Graphics terminal (GraphOn)
      G2  = Graphics terminal (Codonics)
      G3  = Graphics terminal (Micro-term, Versaterm)
      F   = File
      T   = Tektronix 4662 flat bed plotter (1200 baud)
  
 DEVICES=
 G                             
 Do you want to write the function to a SAD file?  (default = Y)
 WRITE=N
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