NAME:
	I2VAL
 PURPOSE:
	Converts the first two bytes of the byte array ARR into a fix integer
 CALLING SEQUENCE:
	I = i2val(ARR)
 INPUTS:
	ARR	byte array (should contain at least 2 elements)
 OUTPUTS:
	I2	short (I2) integer
 CALLED BY:
	PRTHDR, RD_EXB
 PROCEDURE:
	The two bytes of ARR are processed in reverse order
 MODIFICATION HISTORY:

 NAME:
	I4VAL
 PURPOSE:
	Converts the four bytes of the byte array ARR into a long integer
 CALLING SEQUENCE:
	I = i4val(ARR)
 INPUTS:
	ARR	byte array (should have at least four elements)
 OUTPUTS:
	I4	long (I4) integer
 CALLED BY:
	PRTHDR
 PROCEDURE:
	The first four bytes are stored in reverse order in the array. The
	LONG function is used to obtain the long integer value.
 MODIFICATION HISTORY:

 NAME:
	IDLEDIT

 PURPOSE:
	This procedure runs the IDL text editor as a detached sub-process
	or launches it under Unix

 CATEGORY:
	GEN,UTIL,WIDGETS,SYSTEM

 CALLING SEQUENCE:
	IDLEDIT, Filename

 CALLS: ***
	BREAK_PATH [1], BREAK_PATH [2], BREAK_PATH [3], EDITOR, LOC_FILE [1], LOC_FILE [2]
	LOC_FILE [3]
 INPUTS:
               Filename - Fully qualified filename

 OPTIONAL INPUTS:
               Filename - Fully qualified filename otherwise PICKFILE is started
      

 OUTPUTS:
       none explicit, 

 OPTIONAL OUTPUTS:
       none

 KEYWORDS:
       none
 COMMON BLOCKS:
       none

 SIDE EFFECTS:
	A file may be written.

 RESTRICTIONS:
	VMS only at the present, 15-Jul-1996

 PROCEDURE:
	A new idl session is spawned using /nowait

 MODIFICATION HISTORY:
	RAS, GSFC, 15-Jul-1996

 FILE :  if present, save variables to an IDL save file.
	  Will ignore other keywords.

 DATA :  The 6 dimensional data array. 
		For 1x1 experiments :
		 


 CALLS:

 NAME:
	IGAIN

 PURPOSE:
       Retrieve gain state number from the SARS status word. 

 CATEGORY:
       HXRBS

 CALLING SEQUENCE:
       Result = IGAIN(Isars)

 CALLS: ***
	CHECKVAR [1], checkvar [2]
 INPUTS:
       Isars:	SARS value.

 OUTPUTS:
       Result:	Gain state.

 CALLED BY:
	HXARCHIVE
 PROCEDURE:
 	MASK SARS TO RETRIEVE VALUE OF BITS 11-13 (GAIN1).
 	MASK SARS TO RETRIEVE VALUE OF BITS 8-10 (GAIN2). IF GAIN1=
 	GAIN2: ADD 1 TO GAIN1 AND USE GAIN1 ONE AS AN INDEX TO 
 	RETRIEVE GAIN STATE FROM TABLE. IF GAIN1 NOT= GAIN2: MASK
 	SARS TO RETRIEVE VALUE OF BITS 5-7 (GAIN3) AND 2-4 (GAIN4).
 	IF GAIN3=GAIN4: ADD 1 TO GAIN3 AND USE GAIN3 AS AN INDEX TO 
 	RETRIEVE GAIN STATE FROM TABLE. IF GAIN3 NOT=GAIN4: USE DEFAULT
 	GAIN STATE OF 6.

 MODIFICATION HISTORY:
       Written by Shelby Kennard 02/06/85.
	Mod. 03/10/92 by RAS. Modified for IDL version 2.
	Mod. 06/96 by RCJ. Added documentation.