【作业】条件、循环、函数定义、字符串操作练习

一、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。

二、对前面的代码进行优化，用for,while,if,def实现：

1、用循环画五角星

 1 from turtle import*
 2 color("red")
 3 fillcolor("red")
 4 begin_fill()
 5 while True:
 6     forward(200)
 7     right(144)
 8     if abs(pos())<1:
 9         break
10 end_fill()

2、用循环画同心圆

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

3、用while循环画太阳花

 1 import turtle
 2 turtle.color(‘red‘,‘yellow‘)
 3 turtle.begin_fill()
 4 while True:
 5     turtle.forward(200)
 6     turtle.left(170)
 7     if abs(turtle.pos())<1:
 8         break
 9 turtle.end_fill()
10 done()

4、用函数定义画五个五角星

 1 def mystar(z):
 2   turtle.begin_fill()
 3   for i in range(5):
 4     turtle.forward(z)
 5     turtle.right(144)
 6   turtle.end_fill()
 7
 8 def otherstart():
 9   turtle.begin_fill()
10   for i in range(5):
11     turtle.right(144)
12     turtle.forward(35)
13 turtle.end_fill()
14
15 mygoto(-250,125)
16 mystar(125)
17
18 mygoto(-105,165)
19 turtle.left(40)
20 turtle.begin_fill()
21 for i in range(5):
22     turtle.forward(35)
23     turtle.right(144)
24 turtle.end_fill()
25
26 mygoto(-30,135)
27 turtle.right(10)
28 turtle.begin_fill()
29 for i in range(5):
30     turtle.right(144)
31     turtle.forward(35)
32 turtle.end_fill()
33
34 mygoto(-40,75)
35 turtle.left(40)
36 turtle.begin_fill()
37 for i in range(5):
38     turtle.right(144)
39     turtle.forward(35)
40 turtle.end_fill()
41
42 mygoto(-75,20)
43 turtle.right(20)
44 turtle.begin_fill()
45 for i in range(5):
46     turtle.right(144)
47     turtle.forward(35)
48 turtle.end_fill()

5、用函数定义画钻石花瓣的太阳花

 1 from turtle import *
 2 def draw_prismatic():
 3     for i in range(1,3):  #要转三次方向来画一个菱形
 4         forward(100)
 5         right(45)
 6         forward(100)
 7         right(135)
 8
 9 def draw_Diamond_Flower():
10     speed(10)
11     color(‘red‘,‘yellow‘)
12     begin_fill()
13     for i in range(36):
14         draw_prismatic()
15         right(10)
16     end_fill()
17
18 draw_Diamond_Flower()

三、字符串操作

1、输入学号，识别年级、专业、序号。

 1 majors = {
 2  11:‘网络工程‘,
 3  12:‘软件工程‘,
 4  13:‘数字媒体‘,
 5  }
 6
 7 def recognition(studentID):
 8     if len(studentID)<12:
 9         print("请输入正确的学号！")
10     elif studentID.isdigit() != True:
11         print("请输入正确的学号！")
12     else:
13         grade = studentID[0:4]
14         major = studentID[6:8]
15         num = studentID[10:12]
16         print("年级：{}级".format(grade))
17         print("专业为：",majors.get(int(major)))
18         print("序号:{}".format(num))
19
20 studentID = input("请输入学号：")
21 recognition(studentID)

2、输入1-7的数字，输出对应的“星期几”。

3、识别身份证号中的省市区、年龄、性别。

4、用字符串操作生成python文档各库的网址(起始网址在这里https://docs.python.org/3.6/library/index.html)

5、练习字符串的+,*,in,len(),eval()