think python学习心得-（2）接口设计

TurtleWorld模块的下载与安装：

下载地址就是：http://thinkpython.com/swampy

安装方法把压缩包解压之后，用cmd cd到解压的安装目录下，运行：

python setup.py install

安装后就可以from swampy.TurtleWorld import *啦！

练习4.3

1-

from swampy.TurtleWorld import *

world = TurtleWorld()
bob = Turtle()
print bob

def square(t):
    for i in range(4):
        fd(t,100)
        lt(t)

square(bob)
wait_for_user()

2-

from swampy.TurtleWorld import *

world = TurtleWorld()
bob = Turtle()
print bob

def square(t,length):
    for i in range(4):
        fd(t,length)
        lt(t)

square(bob,50)
wait_for_user()

3-

from swampy.TurtleWorld import *

world = TurtleWorld()
bob = Turtle()
print bob

def square(t,length,n):
    for i in range(n):
        fd(t,length)
        lt(t,360/n)

square(bob,50,6)
wait_for_user()

4-

太简单了不写了

5-

直接用math包

画六边形：

from swampy.TurtleWorld import *

world = TurtleWorld()
bob = Turtle()

def square(t,length,n):
    for i in range(n):
        fd(t,length)
        lt(t,360/n)

for i in range(6):    
    square(bob,50,3)
    lt(bob,60)

wait_for_user()