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			       CU

      COMPARGAL is a module which plots two or more galaxy surface brightness
 or color distributions.  Typical uses are for comparing an observed 
 distribution with a seeing convolved fitting function such as the de
 Vaucouleurs formula.

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 Enter an option:                              25-NOV-1991 15:01:47.81
 OPTION=CG                                                                  
 COMPARGAL, Version 3
 Enter a command:
      DD = Plots the normalized difference of integrated surface brightness
           (ADU) between two data files against radius (default)
      DF = Plots the normalized difference of integrated surface
           brightness between two formulas
      RD = Plots the normalized ratio of surface brightness (ADU) between
           two data files
      RF = Plots the normalized ratio of surface brightness between two formulas
      CD = Plots the difference of surface brightness of two data files
           (magnitude).  Error bars and the predicted color from the Modified
           Hubble and de Vaucouleurs formulas, which must exist as files
           (magnitude), are added.
      SD = Plots the simple difference of surface brightness of two
           data files (magnitude or ADU)
      TD = Plots the surface brightnesses (magnitude) of two files
           simultaneously;  error bars may be added to the first.
      OD = Plots the surface brightness (magnitude) of one file;  error bars may
           be added.
  
 COMMAND=CD		    ....We are going to plot the color distribution
				and the predictions of seeing convolved
				fitting formulas
 Open the first data file
 Enter the file name:  (default = last entry)
 FILE_21=M022152		    ....This file, for the blue data, is of 
					type 1 and is in units of magnitudes 
					and arc seconds.
 Enter the ID of the first object:  (default = last entry)
 ID=70
 File M022152 does not begin at the center of the object
 Open the second data file
 Enter the file name:  (default = last entry)
 FILE_22=M022151		    ....This is the red data
 Enter the ID of the second object:  (default = last entry for first object)
 ID_2=
 70    				    ....We took the default
 File M022151 does not begin at the center of the object
 Enter the starting and ending radii for the plot:
 (default = the common range of the data files)
 RADII=
 -0.538000    
   1.94200    			    ....We took the default.  This may
					be too much if the data begins
					to look noisy at large radii
 Enter the readout noise in electrons and the gain in electrons per ADU:
 (defaults = 63.9 21.3)
 NOISE_PARAMETERS=
   63.9000    
   21.3000    
 Enter the original sky levels for the two files:
 SKIES=491.416 318.486		    ....Units of ADU
 Enter the sigmas of the skies of the two files:
 SIGMA_SKY=0.051 0.031		    ....Units of ADU
 Enter the magnitude calibration constants for the two files:
 CALIBRATIONS=27.4212 25.3366	    ....The numbers added to -2.5*log(ADU)
 Enter the plate scale in "/pixel:  (default = 0.6298)
 SCALE=
  0.629800    			    ....The McGraw-Hill 1.3 m
 Enter the smoothing factors:  (defaults = 0.3 0.3)
 SMOOTHING_FACTORS=
  0.300000    
  0.300000    			    ....These are the factors that were
					used in option ED
 Enter the log(r)'s at which error bars are to be placed:
 (default = none
 log(r)'s=-0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4
 Open the first artificial data file for the modified Hubble formula
 Enter the file name:  (default = last entry)
 FILE_23=M022152FM		    ....An artificial data file constructed
					with option FG, the galaxy parameters,
					and the point spread function.  It
					was then edited with option ED to put
					it in units of magntiudes and
					arc seconds.
 Open the second artificial data file for the modified Hubble formula
 Enter the file name:  (default = last entry)
 FILE_24=M022151FM		    ....Same, but for the red.
 File M022152FM does not begin at the center of the object
 File M022151FM does not begin at the center of the object
 For the actual data and the formula:
 Mean error =    0.12251	    ....The program compared the data and
					the formula
 Open the first artificial data file for the de Vaucouleurs formula
 Enter the file name:  (default = last entry)
 FILE_25=M022152FV		    ....Blue
 Open the second artificial data file for the de Vaucouleurs formula
 Enter the file name:  (default = last entry)
 FILE_26=M022151FV		    ....Red
 File M022152FV does not begin at the center of the object
 File M022151FV does not begin at the center of the object
 For the actual data and the formula:
 Mean error =    0.12952
 Enter the title:  (default = ID)
 TITLE=Galaxy 70
 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)
      F   = File
      T   = Tektronix 4662 flat bed plotter (1200 baud)
  
 DEVICES=G
			    ....We now inspect the plot.  It is too noisy
				at large radii.  It is easy to repeat 
				everything with new radii.  Watch.

 Enter an option:                              25-NOV-1991 15:10:28.03
 OPTION=.CG(RADII=-0.538 1.5)                                                           
 COMPARGAL, Version 3
			    ....All the prompts are automatically 
				answered and the plot will appear with
				a smaller range.
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