绘制图形（-）

1.绘制五角星 

import turtle
n = eval(input("请输入五角星的长度"))
turtle.begin_fill() #开始填充颜色
i = 0
while i < 5:
    turtle.forward(n)
    turtle.right(180-36)
    i += 1
turtle.color("blue") # 退出填充颜色
turtle.end_fill()
turtle.done()

2.绘制sinx

import turtle
import math

turtle.speed(0)
turtle.penup()
turtle.goto(-175, 50 * math.sin((-175/100) * 2 * math.pi))
turtle.pendown()
turtle.color("red")
for x in range(-175, 176):

    turtle.goto(x, 50 * math.sin((x/100) * 2 * math.pi))

turtle.color("black")
turtle.penup()
turtle.goto(-100, -15)
turtle.write("-2\u03c0", font=("黑体", 15))
turtle.pendown()

turtle.penup()
turtle.goto(100, 15)
turtle.write("2\u03c0", font=("黑体", 15))
turtle.pendown()

turtle.penup()
turtle.goto(-160, 0)
turtle.pendown()
turtle.goto(160, 0)
turtle.write("x", font=("宋体",15))
turtle.goto(150, 10)
turtle.goto(160, 0)
turtle.goto(150, -10)

turtle.penup()
turtle.goto(0, -160)
turtle.pendown()
turtle.goto(0, 160)
turtle.write("y", font=("宋体",15))
turtle.goto(-10, 150)
turtle.goto(0, 160)
turtle.goto(10, 150)
turtle.done()

3.绘制平方函数

import turtle
import math
turtle.speed(0)

# 画一个平方的函数

turtle.penup()
turtle.goto(-100, 0.01*100*100)
turtle.pendown()
for i in range(-100, 100):
    turtle.goto(i, 0.01*i*i)

turtle.penup()
turtle.goto(-160, 0)
turtle.pendown()
turtle.goto(160, 0)
turtle.write("x", font=("宋体",15))
turtle.goto(150, 10)
turtle.goto(160, 0)
turtle.goto(150, -10)

turtle.penup()
turtle.goto(0, -160)
turtle.pendown()
turtle.goto(0, 160)
turtle.write("y", font=("宋体",15))
turtle.goto(-10, 150)
turtle.goto(0, 160)
turtle.goto(10, 150)



turtle.hideturtle()

turtle.done()