实验4 函数与异常处理编程

实验任务1

task1

 1 print(sum)
 2 sum = 42
 3 print(sum)
 4 
 5 def inc(n):
 6     sum = n+1
 7     print(sum)
 8     return sum
 9 
10 
11 sum = inc(7) + inc(7)
12 print(sum)
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不是同一个对象名称

 1.Built-in。2和3 Global。4.Local

实验任务2

task2-1

 1 def func1(a, b, c, d, e, f):
 2     return [a,b,c,d,e,f]
 3 
 4 
 5 def func2(a, b, c,*, d, e, f):
 6     return [a,b,c,d,e,f]
 7 
 8 
 9 def func3(a, b, c, /, d, e, f):
10     return [a,b,c,d,e,f]
11 
12 
13 # func1调用：按位置传递、按参数传递都可以
14 print( func1(1,9,2,0,5,3) )
15 print( func1(a=1, b=9, c=2, d=0, e=5, f=3) )
16 print( func1(1,9,2, f=3, d=0, e=5))
17 
18 
19 # func2调用：d,e,f必须按关键字传递
20 print( func2(11, 99, 22, d=0, e=55, f=33) )
21 print( func2(a=11, b=99, c=22, d=0, e=55, f=33) )
22 
23 
24 # func3调用：a,b,c必须按位置传递
25 print( func3(111, 999, 222, 0, 555, 333))
26 print( func3(111, 999, 222, d=0, e=555, f=333) )
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 task2-2

1 list1 = [1, 9, 8, 4]
2 print( sorted(list1) )
3 print( sorted(list1, reverse=True) )
4 print( sorted(list1, True) )
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注：reverse的传递方式必须使用关键字。

task2-3

1 def func(a, b, c, /, *, d, e, f):
2     return([a,b,c,d,e,f])
3 
4 
5 print(func(1, 2, 3, d=4, e=5, f=6))
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 实验任务3

 1 def solve(a, b, c):
 2     '''
 3     求解一元二次方程, 返回方程的两个根
 4     :para: a,b,c: float 方程系数
 5     :return: tuple
 6     '''
 7     delta = b*b - 4*a*c
 8     delta_sqrt = abs(delta)**0.5
 9     p1 = -b/2/a
10     p2 = delta_sqrt/2/a
11 
12     if delta >= 0:
13         root1 = p1 + p2
14         root2 = p1 - p2
15     else:
16         root1 = complex(p1, p2)
17         root2 = complex(p1, -p2)
18 
19     return root1, root2
20 
21 
22 print(solve.__doc__)
23 while True:
24     try:
25         t = input('输入一元二次方程系数a b c, 或者，输入#结束:')
26         if t == '#':
27             print('结束计算，退出')
28             break
29         a, b, c = map(float, t.split())
30         if a == 0:
31             raise ValueError('a = 0, 不是一元二次方程')
32     except ValueError as e:
33         print(repr(e))
34         print()
35     except:
36         print('有其它错误发生\n')
37     else:
38         root1, root2 = solve(a, b, c)
39         print(f'root1 ={root1:.2f},root2 = {root2:.2f}')
40         print()
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 实验任务4

task4

 1 # list_generator()函数定义
 2 def list_generator(start, stop, step=1):
 3     result = []
 4     i = start
 5     while i <= stop:
 6         result.append(i)
 7         i += step
 8     return result
 9 
10 
11 list1 = list_generator(-5, 5)
12 print(list1)
13 list2 = list_generator(-5, 5, 2)
14 print(list2)
15 list3 = list_generator(1, 5, 0.5)
16 print(list3)
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实验任务5

task5

 1 def is_prime(x):
 2     for i in range(2,int(x**0.5+2)):
 3         a=x%i
 4         if a==0:
 5             break
 6     if a==0 and x!=2:
 7         return False
 8     elif a!=0 or x==2:
 9         return True
10     
11     
12 for i in range(4,21,2):
13     for x in range(2,i):
14         y = i - x
15         if is_prime(x) and is_prime(y):
16             print(f'{i}={x}+{y}')
17             break
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 实验任务6

task6

 1 def encoder(text):
 2     x1 = ''
 3     for i in text:
 4         if 'a' <= i <= 'z':
 5             i = chr((ord(i)-97+5) % 26 + 97)
 6             x1 += i
 7         elif 'A' <= i <= 'Z':
 8             i = chr((ord(i)-65+5) % 26 + 65)
 9             x1 += i
10         else:x1 += i
11     return x1
12 
13 
14 def decoder(text):
15     x2 = ''
16     for i in text:
17         if 'a' <= i <= 'z':
18             i = chr((ord(i)-97-5) % 26 + 97)
19             x2 += i
20         elif 'A' <= i <= 'Z':
21             i = chr((ord(i)-65-5) % 26 + 65)
22             x2 += i
23         else:
24             x2 += i
25     return x2
26 
27 
28 text = input('输入英文文本: ')
29 encoded_text = encoder(text)
30 print('编码后的文本: ', encoded_text)
31 decoded_text = decoder(encoded_text)
32 print('对编码后的文本解码: ', decoded_text)
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实验任务7

task7

 1 def collatz(n):
 2     lst = []
 3     lst.append(n)
 4     while n != 1:
 5         if n %2 == 0:
 6             n = n/2
 7             lst.append(int(n))
 8         else:
 9             n = n*3 +1
10             lst.append(int(n))
11     return lst
12 try:
13     n = int(input('Enter a positive integer:'))
14     if n <= 0:
15         raise ValueError
16 except ValueError:
17     print('Error: must be a positive integer')
18 else:
19     print(collatz(n))
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实验任务8

task8

 1 def func(a):
 2     if a == 0:
 3         return 0
 4     else:
 5         return 2*func(a-1)+1
 6 
 7 
 8 while True:
 9     x = input()
10     if x == '#':
11         print('计算结束')
12         break
13     n = int(x)
14     ans = func(n)
15     print(f'n = {n}, ans = {ans}')
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posted @ 2023-05-23 12:11  ‘_‘  阅读(27)  评论(0)    收藏  举报