条件、循环、函数定义 练习

1. 注意标准库的两种导入与使用方式，建议大家采用<库名>.<函数名>的方式。

        2. 对前面的代码进行优化，用for,while,if,def实现：

a.画五角星

import turtle
turtle.shape('turtle')
for i in range(5):
    turtle.forward(100)
    turtle.right(144)

             

b.画同心圆

import turtle
for i in range(3):
    turtle.up()
    turtle.goto(0,-20*(i+1))
    turtle.down()
    turtle.circle(20*(i+1))

 

c.画太阳花

import turtle
turtle.color('yellow')
turtle.begin_fill()
while True:
    turtle.forward(250)
    turtle.left(150)
    if(abs(turtle.pos()))<1:
        break
turtle.end_fill()
turtle.done()

 

d.画五个五角星

import turtle
turtle.color('yellow')
turtle.bgcolor('red')
turtle.fillcolor('yellow')

def my_goto(x,y):
    turtle.up()
    turtle.goto(x,y)
    turtle.down()

def my_draw5(r):
    turtle.begin_fill()
    for i in range(5):
        turtle.forward(r)
        turtle.right(144)
    turtle.end_fill()

my_goto(-600,220)
my_draw5(100)

my_goto(-400,295)
turtle.left(50)
my_draw5(50)

my_goto(-350,212)
turtle.left(44)
my_draw5(50)

my_goto(-350,145)
turtle.left(50)
my_draw5(50)

my_goto(-400,90)
turtle.left(50)
my_draw5(50)

turtle.hideturtle()
turtle.done()

 

e.画◇花瓣的太阳花。

import turtle
turtle.fillcolor('yellow')
turtle.pencolor('red')
turtle.begin_fill()

def draw_diamond():
    for i in range(1,3):
        turtle.forward(100)
        turtle.right(45)
        turtle.forward(100)
        turtle.right(135)

for i in range(1,37):
    draw_diamond()
    turtle.right(10)

turtle.end_fill()
tirtle.right(90)
turtle.forward(300)

turtle.hideturtle()