def promote(self, other):
if isinstance(other, Rational):
return other
#if isinstance(other, Poly):
# return other
other = Poly.promote(other, self.base)
other = Rational(self.base, other, self.base.one)
return other
def __init__(self, base, p, q, vs=None):
# f(x) == p(x) / q(x)
# q(x)*f(x) == p(x)
p = Poly.promote(p, base)
q = Poly.promote(q, base)
zero, one = base.zero, base.one
if vs is None:
vs = p.get_vars() + q.get_vars()
vs = list(set(vs))
vs.sort()
n = len(vs)
#assert n>0
#print("Rational(%s, %s, %s)" % (p, q, vs))
fs = {}
vzero = tuple((v,zero) for v in vs)
top = p.substitute(vzero)
bot = q.substitute(vzero)
if bot == 0:
fs = None
else:
#print("top=%s, bot=%s" % (top, bot))
f0 = top/bot
#print("f0:", lstr(f0))
fs[(0,)*n] = f0
self.base = base
self.p = p
self.q = q
self.fs = fs
self.vzero = vzero
self.vs = vs
self.bot = bot