require:

Syntax:	require NAME ...

Description:

	The require command takes Rfile names as operands, and checks
	the workspace for a function variable called NAME. If that
	function exists, then no action is taken. If the function does
	not exist, then the file `NAME.r' is loaded.

	More than one NAME can be given on the same
	line. Continuations are not allowed.

	NAME can contain the `.r' extension that distinguishes Rfiles
	(by convention), or NAME can omit the `.r' extension. In
	either case a workspace variable without the `.r' extension is
	checked for.

	Example:

	> require roots poly.r bode

	The require command syntax is identical to the rfile command,
	with the obvious exception of the initial keyword.

	The rules for searching the user's RLAB_SEARCH_PATH are the
	same as those used with the rfile command.

See Also: COMMAND, KEYWORDS, rfile, load
