实验4 函数与异常处理应用编程
task1.py
1 print(sum) 2 sum = 42 3 print(sum) 4 def inc(n): 5 sum = n+1 6 print(sum) 7 return sum 8 sum = inc(7) + inc(7) 9 print(sum)
不是
1.内置函数2.全局变量3.局部变量4.全局变量
task2_1.py
1 def func1(a, b, c, d, e, f): 2 '''返回参数a,b,c,d,e,f构成的列表 3 默认,参数按位置传递; 也支持关键字传递 4 ''' 5 return [a,b,c,d,e,f] 6 def func2(a, b, c,*, d, e, f): 7 ''' 8 返回参数a,b,c,d,e,f构成的列表 9 *后面的参数只能按关键字传递 10 ''' 11 return [a,b,c,d,e,f] 12 def func3(a, b, c, /, d, e, f): 13 ''' 14 返回参数a,b,c,d,e,f构成的列表 15 /前面的参数只能按位置传递 16 ''' 17 return [a,b,c,d,e,f] 18 print( func1(1,9,2,0,5,3) ) 19 print( func1(a=1, b=9, c=2, d=0, e=5, f=3) ) 20 print( func1(1,9,2, f=3, d=0, e=5)) 21 22 print( func2(11, 99, 22, d=0, e=55, f=33) ) 23 print( func2(a=11, b=99, c=22, d=0, e=55, f=33) ) 24 25 print( func3(111, 999, 222, 0, 555, 333)) 26 print( func3(111, 999, 222, d=0, e=555, f=333) )
task2_2.py
1 list1 = [1, 9, 8, 4] 2 print( sorted(list1) ) 3 print( sorted(list1, reverse=True) ) 4 print( sorted(list1, True) )
是
task2_3.py
def func(a, b, c, /, *, d, e, f): return ([a, b, c, d, e, f]) print(func(1, 2, 3, d=4, e=5, f=6))
task3.py
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: int 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 13 if delta>=0: 14 root1 = p1 + p2 15 root2 = p1 - p2 16 else: 17 root1 = complex(p1, p2) 18 root2 = complex(p1, -p2) 19 20 return root1, root2 21 22 print(solve.__doc__) 23 while True: 24 try: 25 a,b,c = eval(input('Enter eqution coefficient: ')) 26 if a == 0: 27 raise 28 except: 29 print('invalid input, or, a is zero') 30 break 31 else: 32 root1, root2 = solve(a, b, c) 33 print(f'root1 = {root1:.2f}, root2 = {root2:.2f}') 34 print()
task4.py
1 def list_generator(begin, end, step=1): 2 list = [] 3 while begin <= end: 4 list.append(begin) 5 begin = begin + step 6 return list 7 8 9 list1 = list_generator(-5, 5) 10 print(list1) 11 12 list2 = list_generator(-5, 5, 2) 13 print(list2) 14 15 list3 = list_generator(1, 5, 0.5) 16 print(list3)
task5.py
1 def is_prime(n): 2 if n < 2: 3 return False 4 for i in range(2,int(n**0.5)+1): 5 if n % i == 0: 6 return False 7 return True 8 9 h=[i for i in range(21)] 10 for x in h[::2]: 11 for a in range(0,21): 12 if is_prime(a) is True: 13 if is_prime(x-a) is True: 14 print(f'{x}={a}+{x-a}') 15 break 16 else: 17 a+=1 18 else: 19 a+=1
task6.py
def encoder(strs): a=list(strs) i=0 while i <len(strs): b = ord(a[i]) if 65<=b<=85 or 97<=b<=117: c=chr(b+5) elif 85<=b<=90 or 117<=b<=122: c=chr(b-21) else: c=chr(b) a[i]=c i+=1 return ''.join(a) def decoder(strs): a = list(strs) i=0 while i < len(strs): b = ord(a[i]) if 70<=b<=90 or 102<=b<=122: c=chr(b-5) elif 65<=b<=70 or 97<=b<=102: c=chr(b+21) else: c=chr(b) a[i] = c i+=1 return ''.join(a) a=input('输入英文文本: ') print(f'编码后的文本:{encoder(a)}') print(f'对编码后的文本解码:{decoder(encoder(a))}')
task7.py
def collatz(n): x=[n] while n!=1: if n%2==0: n=n/2 else: n=3*n+1 x.append(int(n)) return x try: n=int(input('Enter a positive integer:')) if n<=0: raise except: print('Error: must be a positive integer') else: print(collatz(n))