用蟒蛇繪製花朵

Question

我正在學習用python編程（指的是想想python 2），並且對程序感到驚訝。問題說明：Python program to draw a symmetric flower after seeking the size of and number of petals from user。

我想出的代碼如下，除了我無法得到每個花瓣之間的數學角度正確的部分（代碼附近的代碼狀態bob.lt(360/petal)）。有人可以幫忙嗎？

import math 
radius=int(input("What is the radius of the flower? ")) 
petals=int(input("How many petals do you want? ")) 
#radius=100 
#petals=4 


def draw_arc(b,r): #bob the turtle,corner-to-corner length (radius) of petal (assume 60 degree central angle of sector for simplicity) 
    c=2*math.pi*r #Circumference of circle 
    ca=c/(360/60) #Circumference of arc (assume 60 degree central angle of sector as above) 
    n=int(ca/3)+1 #number of segments 
    l=ca/n #length of segment 
    for i in range(n): 
     b.fd(l) 
     b.lt(360/(n*6)) 

def draw_petal(b,r): 
    draw_arc(b,r) 
    b.lt(180-60) 
    draw_arc(b,r) 

import turtle 
bob=turtle.Turtle() 

#draw_petal(bob,radius) 

for i in range(petals): 
    draw_petal(bob,radius) 
    bob.lt(360/petals) 

turtle.mainloop() 

正確（對稱） 不正確的（非對稱）

Answer 1

只需修改這樣的代碼（在draw_petals添加b.rt(360/petals-30，正確bob.lt(360/petals)到360/4）：

import math 
radius=int(input("What is the radius of the flower? ")) 
petals=int(input("How many petals do you want? ")) 
#radius=100 
#petals=4 


def draw_arc(b,r): #bob the turtle,corner-to-corner length (radius) of petal (assume 60 degree central angle of sector for simplicity) 
    c=2*math.pi*r #Circumference of circle 
    ca=c/(360/60) #Circumference of arc (assume 60 degree central angle of sector as above) 
    n=int(ca/3)+1 #number of segments 
    l=ca/n #length of segment 
    for i in range(n): 
     b.fd(l) 
     b.lt(360/(n*6)) 


def draw_petal(b,r): 
    draw_arc(b,r) 
    b.lt(180-60) 
    draw_arc(b,r) 
    b.rt(360/petals-30) # this will take care of the correct angle b/w petals 


import turtle 
bob=turtle.Turtle() 
#draw_petal(bob,radius) 

for i in range(petals): 
    draw_petal(bob,radius) 
    bob.lt(360/4) 

Answer 2

我認爲問題比你做得更簡單。

第一個問題是繪製花瓣會改變海龜的標題，並且您正在嘗試做數學運算以將其設置回開始位置。在這裏，我們可以在畫花瓣之前記錄標題並在之後恢復，不需要數學。

第二個問題是你實現自己的弧線代碼時，烏龜可以做到這一點使用的程度參數turtle.circle()產生相同的結果，但要快得多：

from turtle import Turtle, Screen 

def draw_petal(turtle, radius): 
    heading = turtle.heading() 
    turtle.circle(radius, 60) 
    turtle.left(120) 
    turtle.circle(radius, 60) 
    turtle.setheading(heading) 

my_radius = int(input("What is the radius of the flower? ")) 
my_petals = int(input("How many petals do you want? ")) 

bob = Turtle() 

for _ in range(my_petals): 
    draw_petal(bob, my_radius) 
    bob.left(360/my_petals) 

bob.hideturtle() 

screen = Screen() 
screen.exitonclick() 

用法

> python3 test.py 
What is the radius of the flower? 100 
How many petals do you want? 10 

輸出