P77-78

正方形螺旋线：
import turtle
pen = turtle.Turtle()
pen.speed(0)

step = 10

for _ in range(50):
pen.forward(step)
pen.right(90)
pen.forward(step)
pen.right(90)
step += 10

turtle.done()

等边三角形：

DrawPython.py

import turtle
turtle.penup()
turtle.fd(-250)
turtle.pendown()
turtle.fd(100)
turtle.left(120)
turtle.fd(100)
turtle.left(120)
turtle.fd(100)

turtle.done()

叠加等边三角形：

DrawPython.py

import turtle
turtle.penup()
turtle.fd(-250)
turtle.pendown()
turtle.fd(100)
turtle.left(120)
turtle.fd(100)
turtle.left(120)
turtle.fd(50)
turtle.left(120)
turtle.fd(50)
turtle.right(120)
turtle.fd(50)
turtle.right(120)
turtle.fd(50)
turtle.left(120)
turtle.fd(50)
turtle.done()

汇率兑换程序：

TempConvert.py

TempStr = input("请输入带有单位的货币值：")
if TempStr[-1] in ['￥']:
C=eval(TempStr[0:-1])/6
print("={:.2f}美元".format(C))
elif TempStr[-1] in ['$']:
F=eval(TempStr[0:-1])*6
print("={:.2f}人民币".format(F))
else :
print("输入格式错误")

六角形：

DrawPython.py

import turtle
turtle.penup()
turtle.left(30)
turtle.pendown()
turtle.fd(300)
turtle.right(120)
turtle.fd(300)
turtle.right(120)
turtle.fd(200)
turtle.right(60)
turtle.fd(200)
turtle.right(120)
turtle.fd(300)
turtle.right(120)
turtle.fd(300)
turtle.right(120)
turtle.fd(100)
turtle.left(60)
turtle.fd(100)

turtle.done()

蟒蛇绘图（彩色版）：

DrawColorfulPython.py

import turtle

colors = ['red', 'orange', 'yellow', 'green', 'cyan', 'blue', 'purple']

turtle.setup(650, 350, 200, 200)
turtle.penup()
turtle.fd(-250)
turtle.pendown()
turtle.pensize(25)
turtle.seth(-40)

for i in range(4):
turtle.pencolor(colors[i % len(colors)])
turtle.circle(40, 80)
turtle.circle(-40, 80)

turtle.pencolor(colors[4 % len(colors)])
turtle.circle(40, 80/2)
turtle.pencolor(colors[5 % len(colors)])
turtle.fd(40)
turtle.pencolor(colors[6 % len(colors)])
turtle.circle(16, 180)
turtle.pencolor(colors[0 % len(colors)])
turtle.fd(40 * 2/3)

turtle.done()

温度转换4.0：

TempConvert.py

TempStr = eval(input("请输入温度值："))
unit = input("请输入符号：")
if unit in ['f','F']:
C=(TempStr -32)/1.8
print("转换后的温度是{}C".format(int(round(C))))
elif unit in ['c','C']:
F=1.8*TempStr +32
print("转换后的温度是{}F".format(int(round(F))))
else :
print("输入格式错误")