ChangeLog for merge
===============================
Open SPRs:
- none

Version 0.11 - 2003-12-02 (HB)
 + (src/merge_mod.f90): TSTOP keyword was not updated correctly; fixed.
closed SPR:
 + SSC-SPR-3158: "merge" does not update the TSTOP keyword
	
Version 0.10 - 2003-05-07 (HB)	
-----------------------------------
 + (config/merge.par): modified to enable param-2.0 functionality	
		
Version 0.9  - 2003-04-04 (HB)
-----------------------------------
 + (doc/merge_description.tex): LaTeX error corrected	
	
Version 0.8  - 2003-03-24 (HB)
-----------------------------------
 + (src/merge_mod.f90): merging of additional user-specified event table columns
 + (doc/merge_description.tex): updated	
		
Version 0.7  - 2002-08-21 (AMR/MJF)
-----------------------------------
 + (src/merge_mod.f90): implemented changes as in version 0.4.5 [SSC-SPR-2933,
   and further fix for SSC-SPR-2905]
 + (doc/merge_description.tex): updated
closed SPR:
 + SSC-SPR-2933: Should propagate WEIGHT

Version 0.6  - 2002-07-17 (AMR/MJF)
-----------------------------------
 + (DEPEND): added "sas" as required by new infrastructure (sas-1.302)
 + (src/merge_mod.f90): implemented changes as in versions 0.4.3 and 0.4.4 to
   fix problems with time related keywords
closed SPR:
 + SSC-SPR-2905: LIVETIME header in merged file is not being updated correctly

Version 0.5  - 2002-05-27 (MJF)
-------------------------------
 + (config/merge.par): updated for `param-2.0'
 + (DEPEND): needs `param-2.0', updated all other entries to latest

Version 0.4.2 2002-05-27 (AMR)
-------------
 + (src/merge_mod.f90) Further start/stop time attributes and durations corrected
 + (doc/merge_description.tex) Updated

Version 0.4.1 2001-11-08 (AMR)
-------------
 + (src/merge_mod.f90) STDGTI files now merged (SSC-SPR-2617). 
   Various start & stop time attributes corrected
 + (doc/merge_description.tex) Updated

Version 0.4 2001-06-19 (AMR)
-------------
	+ (src/merge_mod.f90) New functionality, allowing adjustments of 
	  individual event file sky coordinates, for attitude errors etc, prior
   to merging. 
	+ (config/merge.par, merge.lyt) New parameters for sky coordinate 
	  adjustments. Also withuserradec changed to withradec. 
 + (doc/merge_description.tex) Above change described. 

Version 0.3.1 2000-11-23 (AMR)
-------------
 + (doc/merge_description.tex) Documentation updated (SSC-SPR-2115)

Version 0.3 2000-09-22 (AMR)
------------

Initial SAS version - non-accepted (version number same as documentation). 
Experimental and under development - treat all output with caution. 
Comments welcome, especially as regards improvements in output file. 

Examples:
---------	
>  Merging two event files (reprojecting X/Y coordinates to mean ref.point)

merge set1=ev1.fits set2=ev2.fits outset=evout.fits

>  Merging two event files (reprojecting X/Y coordinates to user ref.point)

merge set1=ev1.fits set2=ev2.fits outset=evout.fits withuserradec=Y ra=10.2 dec=-13.7

>  Merging two attitude files (atthkgen output files)

merge set1=att1.fits set2=att2.fits outset=attout.fits

>  Merging two orbit files (orbit output files)

merge set1=orb1.fits set2=orb2.fits outset=orbout.fits

-- Note, it is possible in many cases to treat the output files as ordinary 
(non-merged) files. e.g. creation of an exposure map is possible for merged 
data: First merge the relevant event files and associated attitude files, then 
form a sky image (via evselect) from the merged event file, then run eexpmap
as normal using this image and the merged event and attitude files. 
-- Just to reiterate, do take care with any merged output. This task is still 
under development.