PRO array_arith

	; scalar addition 
	a = 2.0
	b = 3.0
	print, 'a = ', a
	print, 'b = ', b
	print
	print, 'a+b = ', a+b
	print

	c = [1.,3.,5.,7.]
	d = [2.,2.,2.,2.]
	
	print, 'c = ', c
	print, 'd = ', d
	print
	; array addition/multiplication 
	print, 'c+d = ', c+d
	print
	print, 'c*d = ', c*d
	print
	; if any one of the variabiles in an expression is an array, the result will be an array
	print, 'c*a = ', c*a
	print
	e = [10,10]
	f = [1,2,3,4,5]
	print, 'e = ', e
	print, 'f = ', f
	print
	;if an expression contains arrays of different sizes, the result array will have as many elements 
	;as the smallest array in the expression 
	print,'e*f = ', e*f
	g = FLTARR(10)+10.
	h = INDGEN(3,2)
	print, 'g = ', g
	print, 'h = '
	print, h
	print
	print,'g*h = '
	print, g*h
	print
	;if an expression contains arrays with different numbers of elements and dimensions, the result array
	; will have as many elements and as many dimensions as the smallest array in the expression
	j = FLTARR(4)+10
	k = INDGEN(2,2)
	
	print, 'j = ', j
	print, 'k = '
	print, k
	print
	;if an expression contains arras with the same number of elements but different dimensions, 
	;the result array will have as many dimensions as the leftmost array in the expression 
	print, 'j*k = '
	print,j*k
	print
	print,'k*j = '
	print, k*j
	print

END