import random
def ftree(rows, v, i, F):
if len(v) > 0:
rows.append(v)
w = []
for i in range(len(v)):
k, _, _ = v[i]
if k is None or is_prime(k):
w.append((None,None,None))
else:
d = random.choice(divisors(k)[1:-1])
w.append((d,k,i))
e = k//d
if e == 1:
w.append((None,None))
else:
w.append((e,k,i))
if len(w) > len(v):
ftree(rows, w, i+1, F)
def draw_ftree(rows,font):
g = Graphics()
for i in range(len(rows)):
cur = rows[i]
for j in range(len(cur)):
e, f, k = cur[j]
if not e is None:
if is_prime(e):
c = (1,0,0)
else:
c = (0,0,.4)
g += text(str(e), (j*2-len(cur),-i), fontsize=font, rgbcolor=c)
if not k is None and not f is None:
g += line([(j*2-len(cur),-i), ((k*2)-len(rows[i-1]),-i+1)],
alpha=0.5)
return g
@interact
def factor_tree(n=100, font=(10, (8..20)), redraw=['Redraw']):
n = Integer(n)
rows = []
v = [(n,None,0)]
ftree(rows, v, 0, factor(n))
show(draw_ftree(rows, font), axes=False)