питона 3,4 спирографа ошибка

Question

from turtle import*                  
from math import* 

def Xcord(R,r,p,t): 

    x= (R-r) * cos(t) - (r+p) * cos((R-r)//r*t) 

def Ycord (R,r,p,t): 

    y= (R-r) * sin(t) - (r+p) * sin((R-r)//r*t) 

def t_iter(R,r,p): 

     t=0 
     down() 
     goto(Xcord(R,r,p,t),Ycord(R,r,p,t)) 
     while (t < 2 * pi): 
      t = t+.01 
      Xcord(R,r,p,t) 
      Ycord(R,r,p,t) 
      up() 
     return 

def main(): 

     R=100 
     r=4 
     p=int(input("Please enter a number between 10 and 100: ")) 
     if p < 10 or p > 100: 
      input(" Incorrect value of p!") 
     t_iter(R,r,p) 
     input("Hit enter to close porgram") 
     bye() 

main() 

Я получаю эту ошибку:

Traceback (most recent call last): 

    File "C:/Users/Coscio/Desktop/spirals.py", line 31, in <module> 
    main() 

    File "C:/Users/Coscio/Desktop/spirals.py", line 27, in main 
    t_iter(R,r,p) 

    File "C:/Users/Coscio/Desktop/spirals.py", line 13, in t_iter 
    goto(Xcord(R,r,p,t),Ycord(R,r,p,t)) 

    File "<string>", line 1, in goto 

    File "D:\Python\lib\turtle.py", line 1774, in goto 
    self._goto(Vec2D(*x)) 

TypeError: type object argument after * must be a sequence, not NoneType 

Answer 1

from turtle import* 

from math import* 

def Xcord(R,r,p,t): 

     return (R-r) * cos(t) - (r+p) * cos((R-r)//r*t) 

def Ycord (R,r,p,t): 
    return (R-r) * sin(t) - (r+p) * sin((R-r)//r*t) 

def t_iter(R,r,p): 
    t=0 
    up() 
    Xcord(R,r,p,t) 
    Ycord(R,r,p,t) 
    while (t < 2 * pi): 
     t = t+.01 
     goto(Xcord(R,r,p,t),Ycord(R,r,p,t)) 
     down() 
    return float(Xcord(R,r,p,t)) 
    return float(Ycord(R,r,p,t)) 

def validate(): 
    while True: 
     p=int(input("Please enter a number between 10 and 100: ")) 
     if p >= 10 or p <= 100: 
      break 
    return p 


def main(): 
    speed(0) 
    R=100 
    r=4 
    p = validate() 
    t_iter(R,r,p) 
    Xcord(R,r,p,t_iter(R,r,p)) 
    Ycord(R,r,p,t_iter(R,r,p)) 
    input("Hit enter to close porgram") 
    bye() 

main()