NAME:    
	plot_hardness
  PURPOSE: 
	plot hardness ratios to screen or ps file from an xmm database 
  CALLING SEQUENCE: 
	plot_hardness,db[,outfile=outfile,offmax=offmax]
  INPUTS: 
	db: 	name of xmm database to search
 OPTIONAL INPUT PARAMETERS
	OFFMAX: max offax angle of xmm objects to be included. 	f not set
		all xmm objects are included
  OPTIONAL OUTPUT PARAMETERS: 
    	ps: optional output ps file the plots will be sent to. 
		will be put in current_dir/html/xmm/
	gif:as above for gif output, but without the .gif bit.
		only active if ps is not set
       If neither is set, the plots will be sent to screen.
  EXAMPLE: 
	plot_hardness, 'xmmdb',outfile='hardness.ps',offmax='10'
  RESTRICTIONS: 
        UNTESTED
  CALLED PROCEDURES AND FUNCTIONS: 
	astrolib functions
	select_offax, select_cond,ops,cps
  MODIFICATION HISTORY: 
     	09-Oct_2000  Original by Suzanne Aigrain

(See /home/xmmssc/soft/idl/pro/xmm_plots/plot_hardness.pro)