Algebrite/sources/denominator.coffee at 51d40342210d7b4dc574bc1a27fcf28613eb624c · davidedc/Algebrite · GitHub

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### denominator =====================================================================

Tags
----
scripting, JS, internal, treenode, general concept

Parameters
----------
x

General description
-------------------
Returns the denominator of expression x.

###


Eval_denominator = ->
	push(cadr(p1))
	Eval()
	denominator()

denominator = ->
	h = 0

	theArgument = pop()
	#console.trace "denominator of: " + theArgument

	if (car(theArgument) == symbol(ADD))
		push(theArgument)
		rationalize()
		theArgument = pop()

	if (car(theArgument) == symbol(MULTIPLY) and !isplusone(car(cdr(theArgument))))
		h = tos
		theArgument = cdr(theArgument)
		while (iscons(theArgument))
			push(car(theArgument))
			denominator()
			theArgument = cdr(theArgument)
		multiply_all(tos - h)
	else if (isrational(theArgument))
		push(theArgument)
		mp_denominator()
	else if (car(theArgument) == symbol(POWER) && isnegativeterm(caddr(theArgument)))
		push(theArgument)
		reciprocate()
	else
		push(one)