	(INTERNAL-ARRAY)

	Syntax:    H0 (header-word)
		   H1 (header-word)
		   H2 (header-word)
		   H3 (header-word)
		   H4 (header-word)
		   H5 (header-word)
		   H6 (header-word)
		   H7 (header-word)
		   H8 (header-word)
		   H9 (header-word)

	H0 through H9 are internal-array verbs which return or set the
	value contained within elements of the header for internal
	Arrays (0) through (9).  You should reference the header values
	by header keyword names (see the documentation for Keywords for a 
	list of available keyword adverbs).

	If the verb appears to the left of an equal sign, than the
	specified header parameter has its value changed to the value
	of the expression to the right of the equal sign.

	If the verb appears in an expression or as an argument to a
	verb or procedure, then the value of the specified header
	parameter for that array is returned.

	If H0 through H9 is not to the left of an equal sign, and if
	the argument you supply H0 through H9 is a keyword adverb that
	refers to a real-valued header parameter, then H0 through H9
	will return a floating-point value.

	If H0 through H9 is not to the left of an equal sign, and if
	the argument you supply H0 through H9 is a keyword adverb that
	refers to a string header parameter, then H0 through H9 will
	return a string.

	If H0 through H9 is to the left of an equal sign, and if the
	argument you supply H0 through H9 is a keyword adverb that
	refers to a real-valued header parameter, then you should
	supply a real-valued expression to the right of the equal
	sign.

	If H0 through H9 is to the left of an equal sign, and if the
	argument you supply H0 through H9 is a keyword adverb that
	refers to a string header parameter, then you should supply a
	string expression to the right of the equal sign.

	No adverbs are used or set by H0 through H9.

	See the description of internal-array verbs for restrictions on
	their use.

	EXAMPLES:

	.  For real-valued header parameters:

		PRINT H0(SCAN)		

	   Will print scan number of Array(0).

		X = SIN(H1(EL)/57.295)  

	   Will assign to X the value of the sine of the elevation in the
	   header of Array (1).

		H0(STSYS) = SQRT(H8(STSYS)*H7(RTSYS))	
					
	   Changes the value of the system temperature in Array (0) to the
	   square root of the system temperature in Array 8 times the
	   value of the reference system temperature in Array 7.

	.  For string header parameters

		PRINT H1(OBSERVER)   
	
	   Will print the name of the observer for the header in Array
	   (1).
		
		XTITLE = CONCAT('Obj:',H9(OBJECT))

	   Will assign to XTITLE the concatenation of the string 'Obj:'
	   with the name of the observed object for the header of Array
	   (9).

		H0(BACKEND) = '1024 AC' 

	   Changes the value of the back-end designation for the header
	   in Array (0) to the string '1024 AC'.
