FUNCTION SetRange, default, range, lower_limit=lower_limit

;+
; NAME:
;	SetRange
; PURPOSE:
;	Set range of values, checking against a default range
; CATEGORY:
;	Tricks
; CALLING SEQUENCE:
;	new = SetRange(default, range [, /lower_limit])
; INPUTS:
;	default			array[2]; type: any
;						upper and lower limits on allowed values
; OPTIONAL INPUT PARAMETERS:
;	range			scalar or array[2]
;						range to be checked against 'default'
;	/lower_limit	if set then a scalar 'range' is interpreted as
;					a lower limit (default is upper limit)
; OUTPUTS:
;	new				array[2]
;						updated range of values
;						if 'range' undefined then 'new' is set to 'default'
;						if 'range' is scalar then new = [range,default[1]] is
;						returned (/lower_limit is set), or new = [default[0],range[1]]
;						is returned (/lower_limit not set
;						Always 'range' is constrained to stay inside the limits set by 'default'
; INCLUDE:
	@compile_opt.pro		; On error, return to caller
; PROCEDURE:
;	Trivial
; MODIFICATION HISTORY:
;	JUN-2000, Paul Hick (UCSD/CASS; pphick@ucsd.edu)
;-

InitVar, lower_limit, /key

CASE n_elements(range) OF
0   : new = default
1   : IF lower_limit THEN new = [range[0] > default[0], default[1]]	ELSE new = [default[0], range[1] < default[1]]
ELSE: new = [range[0] > default[0], range[1] < default[1]]
ENDCASE

RETURN, new  &  END