第二次运行代码时Python中的Traceback错误

Question

我目前正在编写一个三角形计算器，该计算器可以根据用户的输入求解三角形，并使用Turtle绘制三角形。 但是，尽管它在第一个三角形中正常运行，但是当代码重复其自身并询问用户是否要绘制另一个三角形时，我遇到了一个错误。

这是我到目前为止的代码：

import math
import turtle


def ImpossibleTriangle():
    print ""
    print("That Triangle is imposssible, please try again: ")
    print ""
    return SSS()

def AngleLarge():
    AngleSize = int(input("That angle is too large, Try again: "))
    return AngleSize

def AngleZero():
    AngleSize = int(input("The angle cannot be zero, Try again: "))
    return AngleSize

def SideZero():
    ZeroLength = int(input("The length cannot be zero, Try again: "))
    return ZeroLength

def Sine(side, angleA, angleC):
    ExtraSide = abs(side*(math.sin(math.degrees(angleA)))/math.sin(math.degrees(angleC)))
    return ExtraSide # 'abs' used incase inputted values are negative

# Triangle given two angles and a side not between them

def AAS():
    print ""
    angleA = int(input("Please enter your first angle: "))

    while angleA>178:           # Angle cannot be greater than 178 because this
        angleA = AngleLarge()   # means that the other angles are not int but are floats
    while angleA == 0:
        angleA = AngleZero()
    else:
        angleC = int(input("Please enter your second angle: "))
        while (angleA+angleC)>179: # Again if it is >179 angleB will be a float
            angleC = AngleLarge()
        while angleC == 0:
            angleC = AngleZero()
    angleB = (180-(angleA + angleC)) # Calculates remaining angle
    sidec = int(input("Please enter the known side: "))
    sidea = Sine(sidec, angleA, angleC)
    sideb = Sine(sidec, angleB, angleC)

    sketch(sidea, sideb, sidec, angleA, angleB, angleC)

# Triangle with two angles and a side between them

def ASA():
    print ""
    angleA = int(input("Please enter you first angle: "))
    while angleA>=178:
        angleA = AngleLarge()
    while angleA == 0:
        angleA = AngleZero()
    angleB = int(input("Please enter your second angle: "))
    while (angleA + angleB) > 178:
        angleB = AngleLarge()
    while angleB == 0:
        angleB = AngleZero()
    angleC = (180-(angleA + angleB))

    sidec = int(input("Please enter the known side: "))
    while sidec == 0:
        sidec = SideZero()
    sidea = Sine(sidec, angleA, angleC)
    sideb = Sine(sidec, angleB, angleC)

    sketch(sidea, sideb, sidec, angleA, angleB, angleC)

# Triangle with only sides

def SSS():
    print ""
    sidea = int(input("Please enter your first side: "))
    while sidea == 0:
        sidea = SideZero()
    sideb = int(input("Please enter your second side: "))
    while sideb == 0:
        sideb = SideZero()
    sidec = int(input("Please enter your third side: "))
    while sidec == 0:
        sidec = SideZero()

    while sidea + sideb <= sidec or sideb + sidec <= sidea or sidea + sidec <= sideb:
        sidea, sideb, sidec = ImpossibleTriangle()

    angleA = int(math.degrees(math.acos(float(((sideb*sideb)+(sidec*sidec)-(sidea*sidea)))/float((2*sideb*sidec)))))
    angleB = int(math.degrees(math.acos(float(((sidec*sidec)+(sidea*sidea)-(sideb*sideb)))/float((2*sidec*sidea)))))
    angleC = (180-(angleA + angleB))

    sketch(sidea, sideb, sidec, angleA, angleB, angleC)

# Stating all values calculated, telling the user all information: 

def sketch(sidea, sideb, sidec, angleA, angleB, angleC):
    sidea = round(sidea,1)      # These lines round the decimal place
    sideb = round(sideb,1)      # of each of the known values to 'x'.
    sidec = round(sidec,1)      # If the values were not rounded then
    print ""
    print("These are the sides of your Triangle: - a, b, c -")
    print(sidea, sideb, sidec)


    angleA = round(angleA,1)    # it would result in the code printing 
    angleB = round(angleB,1)    # a longer string that we desire 
    angleC = round(angleC,1)    # it can be altered by changing the value. "1"
    print ""
    print("These are the angles of your Triangle: - A, B, C -")
    print(angleA, angleB, angleC)

# Drawing each line (direction and distance)

    TD = turtle.Turtle() # TD = Triangle Drawing

    TD.speed(1)          # This isn't important, though it can be used later
                         # in the GUI if desired...
    TD.forward(sidea)
    TD.left(180-angleC)
    TD.forward(sideb)
    TD.left(180-angleA)    
    TD.goto(0,0)

    turtle.Screen().exitonclick()

    return home2()

# Home Page

def Terminate():
    Quit = raw_input("Are you sure you want to quit? ")
    if Quit == "Yes" or Quit == "yes" or Quit == "y" or Quit == "Y":
        print ("Thankyou, Goodbye")
        exit()
    elif Quit == "No" or Quit == "no" or Quit == "n" or Quit == "N":
        print("Okay Great!")
        return TriangleFunc()

def TriangleFunc():
    print ""
    print ("Press Q to quit: ")
    Triangle = raw_input("How would you like to draw the triangle? - ASA, AAS, SSS - ")
    if Triangle == "ASA" or Triangle == "asa":
        ASA()
    elif Triangle == "AAS" or Triangle == "aas":
        AAS()
    elif Triangle == "SSS" or Triangle == "sss":
        SSS()
    elif Triangle == "Q" or Triangle == "q" or Triangle == "Quit" or Triangle == "quit":
        Terminate() # Convert this to a list?
    else:
        print("That value isn't valid - Please try again: ")
        TriangleFunc()

def home():
    Answer = raw_input("Would you like to draw a triangle? - (Yes/No) - ")
    if Answer == "Yes" or Answer == "yes" or Answer == "Y" or Answer == "y":
        TriangleFunc()        
    else:
        End = raw_input("Are you sure you want to quit? ")
        if End == "Yes" or End == "yes" or End =="Y" or End == "y":
            print ("Thankyou, Goodbye")
            exit()
        elif End == "No" or End == "no" or End =="N" or End == "n":
            return home()

def home2():
    print ""
    print("------AGAIN?-------")
    User = raw_input("Would you like to draw another Triangle? ")
    if User == "Yes" or User == "yes" or User == "Y" or User == "y":
        TriangleFunc()
    elif User == "No" or User == "no" or User =="N" or User == "n":
        Terminate()

home()

当用户完成输入第二个三角形的值时，这是我收到的错误：

Traceback (most recent call last):
  File "C:\Users\Path to program.py", line 179, in <module>
    home()
  File "C:\Users\Path to program.py", line 161, in home
    TriangleFunc()
  File "C:\Users\Path to program.py", line 147, in TriangleFunc
    ASA()
  File "C:\Users\Path to program.py", line 72, in ASA
    sketch(sidea, sideb, sidec, angleA, angleB, angleC)
  File "C:\Users\Path to program.py", line 129, in sketch
    return home2()
  File "C:\Users\Path to program.py", line 175, in home2
    TriangleFunc()
  File "C:\Users\Path to program.py", line 149, in TriangleFunc
    AAS()
  File "C:\Users\Path to program.py", line 48, in AAS
    sketch(sidea, sideb, sidec, angleA, angleB, angleC)
  File "C:\Users\Path to program.py", line 117, in sketch
    TD = turtle.Turtle() # TD = Triangle Drawing
  File "C:\Python27\lib\lib-tk\turtle.py", line 3707, in __init__
    visible=visible)
  File "C:\Python27\lib\lib-tk\turtle.py", line 2462, in __init__
    self._update()
  File "C:\Python27\lib\lib-tk\turtle.py", line 2565, in _update
    self._update_data()
  File "C:\Python27\lib\lib-tk\turtle.py", line 2551, in _update_data
    self.screen._incrementudc()
  File "C:\Python27\lib\lib-tk\turtle.py", line 1240, in _incrementudc
    raise Terminator
Terminator

对于没有任何潜在解决方案而转储此代码块，我深表歉意，但我真的不知道可能是什么问题。 预先感谢您，Noahf99

Answer 1

问题是您调用了turtle.Screen().exitonclick() sketch() 。 调用此方法后，您将控制权移交给tkinter，您将无法取回它。 在调用home()之后，将此调用移动到文件的末尾。 或者，如果您希望在用户第二次确认要退出后关闭窗口，则将其完全关闭。

这个问题与单例无关，因此我会忽略该建议。