Question

我试图测试我的三角形类，特别是在draw_triangle函数但是一直得到错误：＆＃34;非绑定方法forward（）必须使用Turtle实例作为第一个参数调用（改为使用int实例）＆＃34 ;.我该如何解决这个问题？

from __future__ import print_function, division
from math import sqrt, degrees, acos
import turtle


class Triangle():
    def __init__(self, a = None, b = None, c = None):
        self.a = a;
        self.b = b;
        self.c = c;

def is_triangle(self):
    s = 0.5 * (self.a + self.b + self.c)
    return (s - self.a) > 0 and (s - self.b) > 0 and (s - self.c) > 0

def perimeter(self):
    return self.a + self.b + self.c

def area(self):
    s = 0.5 * (self.a + self.b + self.c)
    return sqrt(s * (s - self.a) * (s - self.b) * (s - self.c))

def a_angle(self):
    return degrees(acos((self.b ** 2 + self.c ** 2 - self.a ** 2) / (2.0 * self.b * self.c)))

def b_angle(self):
    return degrees(acos((self.a ** 2 + self.c ** 2 - self.b ** 2) / (2.0 * self.a * self.c)))

def c_angle(self):
    return degrees(acos((self.a ** 2 + self.b ** 2 - self.c ** 2) / (2.0 * self.a * self.b)))

def angles(self):
    angA = a_angle(self)
    angB = b_angle(self)
    angC = c_angle(self)
    return angA, angB, angC

def __str__(self):
    return 'lengths =  %d, %d, %d' % (self.a, self.b, self.c) + \
           ', perimeter = %d' % (perimeter(self)) + \
           ', area = %d' % (area(self)) + ', angles = %d' % (angles(self))

def draw_triangle(self):
    window = turtle.Screen()
    t = turtle.Turtle
    t.forward(self.c)
    t.left(180 - a_angle(self))
    t.forward(self.a)
    t.left(180 - b_angle(self))
    t.forward(self.b)
    t.done()
    window.exitonclick()

if __name__ == '__main__':
    triangle1 = Triangle(100,100,72)
    triangle2 = Triangle(100,100,100*sqrt(2))
    triangle3 = Triangle(100,50,50)
    print (triangle1)
    print (triangle2)
    print (triangle3)
    Triangle.draw_triangle(triangle1)
    Triangle.draw_triangle(triangle2)
    Triangle.draw_triangle(triangle3)
    turtle.mainloop()

Answer 1

这似乎有效：

from __future__ import print_function, division
from math import sqrt, degrees, acos
import turtle


class Triangle():
    def __init__(self, a = None, b = None, c = None):
        self.a = a;
        self.b = b;
        self.c = c;

    def is_triangle(self):
        s = 0.5 * (self.a + self.b + self.c)
        return (s - self.a) > 0 and (s - self.b) > 0 and (s - self.c) > 0

    def perimeter(self):
        return self.a + self.b + self.c

    def area(self):
        s = 0.5 * (self.a + self.b + self.c)
        return sqrt(s * (s - self.a) * (s - self.b) * (s - self.c))

    def a_angle(self):
        return degrees(acos((self.b ** 2 + self.c ** 2 - self.a ** 2) / (2.0 * self.b * self.c)))

    def b_angle(self):
        return degrees(acos((self.a ** 2 + self.c ** 2 - self.b ** 2) / (2.0 * self.a * self.c)))

    def c_angle(self):
        return degrees(acos((self.a ** 2 + self.b ** 2 - self.c ** 2) / (2.0 * self.a * self.b)))

    def angles(self):
        angA = self.a_angle()
        angB = self.b_angle()
        angC = self.c_angle()
        return angA, angB, angC

    def __str__(self):
        return 'lengths =  %d, %d, %d' % (self.a, self.b, self.c) + \
               ', perimeter = %d' % (self.perimeter()) + \
               ', area = %d' % (self.area()) + ', angles = %d %d %d' % (self.angles())

    def draw_triangle(self):
        window = turtle.Screen()
        t = turtle.Turtle
        t.forward(self.c)
        t.left(180 - self.a_angle(self))
        t.forward(self.a)
        t.left(180 - self.b_angle(self))
        t.forward(self.b)
        t.done()
        window.exitonclick()

if __name__ == '__main__':
    triangle1 = Triangle(100,100,72)
    triangle2 = Triangle(100,100,100*sqrt(2))
    triangle3 = Triangle(100,50,50)
    print (triangle1)
    print (triangle2)
    print (triangle3)

你需要＆＃34;自我。＆＃34;在方法调用前面

这是一个稍微修改过的draw_triangle函数。它运行，但可能并不完全符合您的要求。

    def draw_triangle(self):
        window = turtle.Screen()
        t = turtle.Turtle()
        t.forward(self.c)
        t.left(180 - self.a_angle())
        t.forward(self.a)
        t.left(180 - self.b_angle())
        t.forward(self.b)
        turtle.done()
        window.exitonclick()

我认为你现在应该自己动手。

如何修复此代码中的错误（Python中的Triangle类）？

1 个答案: