实验四 函数于与异常处理编程

1.实验任务1

task1.py

print(sum)
sum = 42
print(sum)

def inc(n):
    sum = n+1
    print(sum)
    return sum

sum = inc(7) + inc(7)
print(sum)

 

2.实验任务2

task2_1.py

def func1(a,b,c,d,e,f):
    '''
    返回参数aa,b,c,d,e,f构成的列表
    默认，参数按位置传递；也支持关键字传递
    '''

    return [a,b,c,d,e,f]

def func2(a,b,c,*,d,e,f):
    '''

    返回参数a,b,c,d,e,f构成的列表
    *后面的参数只能安关键字传递
    '''

    return [a,b,c,d,e,f]



def func3(a,b,c,/,d,e,f):
    '''

    返回参数a,b,c,d,e,f构成的列表
    /前面的参数只能按位子传递
    '''

    return [a,b,c,d,e,f]


#func1调用：按位置传递、按参数传递都可以
print( func1(1,9,2,0,5,3) )
print( func1(a=1,b=9,c=2,d=0,e=5,f=3) )
print( func1(1,9,2,f=3,d=0,e=5) )

#func2调用：d,e,f必须按关键字传递
print( func2(11,99,22,d=0,e=55,f=33) )
print( func2(a=11,b=99,c=22,d=0,e=55,f=33) )

#func3调用：a,b,c必须按位置传递
print( func3(111,999,222,0,555,333) )
print( func3(111,999,222,d=0,e=555,f=333) )

task2_2.py

1 list1 = [1,9,8,4]
2 
3 print( sorted(list1) )
4 print( sorted(list1,reverse=True) )
5 print( sorted(list1,True) )

 

 task2_3.py

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

 

 

3.实验任务3

task3.py

def solve(a,b,c):
    '''
    求解一元二次方程，返回方程的两个根

    ：para:a,b,c: float 方程系数
    ：return: tuple
    '''
    delta = b*b - 4*a*c
    delta_sqrt = abs(delta)**0.5
    p1 = -b/2/a
    p2 = delta_sqrt/2/a

    if delta >= 0:
        root1 = p1 + p2
        root2 = p1 - p2
    else:
        root1 = complex(p1,p2)
        root2 = complex(p1,-p2)

    return root1,root2


while True:
    try:
        t = input('输入一元二次方程系数a b c,或者，输入#结束：')
        if t == '#':
            print('结束计算，退出')
            break
        a,b,c = map(float,t.split())
        if a == 0:
            raise ValueError('a = 0,不是一元二次方程')
    except ValueError as e:
        print(repr(e))
        print()
    except:
        print('有其他错误发生\n')
    else:
        root1,root2 = solve(a,b,c)
        print(f'root1 = {root1:.2f},root2 = {root2:.2f}')
        print()

 

def solve(a,b,c):
    '''
    求解一元二次方程，返回方程的两个根

    ：para:a,b,c: float 方程系数
    ：return: tuple
    '''
    delta = b*b - 4*a*c
    delta_sqrt = abs(delta)**0.5
    p1 = -b/2/a
    p2 = delta_sqrt/2/a

    if delta >= 0:
        root1 = p1 + p2
        root2 = p1 - p2
    else:
        root1 = complex(p1,p2)
        root2 = complex(p1,-p2)

    return root1,root2

print(solve.__doc__)
while True:
    try:
        t = input('输入一元二次方程系数a b c,或者，输入#结束：')
        if t == '#':
            print('结束计算，退出')
            break
        a,b,c = map(float,t.split())
        if a == 0:
            raise ValueError('a = 0,不是一元二次方程')
    except ValueError as e:
        print(repr(e))
        print()
    except:
        print('有其他错误发生\n')
    else:
        root1,root2 = solve(a,b,c)
        print(f'root1 = {root1:.2f},root2 = {root2:.2f}')
        print()

 

 4.实验任务4

task4.py

def list_generator(n,m,i=1):
    list = []
    j = n
    while j <= m:
        list.append(j)
        j+=i
    return list

list1 = list_generator(-5,5)
print(list1)

list2 = list_generator(-5,5,2)
print(list2)

list3 = list_generator(1,5,0.5)
print(list3)

5.实验任务5

task5.py

def is_prime(n):
    if n<= 1:
        return False
    for i in range(2,int(n**0.5)+1):
        if n % i==0:
            return False
    return True

for n in range(21):
    if n % 2 == 0:
        for i in range(21):
            ans1 = is_prime(i)
            if ans1 == True:
                j = n - i
                ans2 = is_prime(j)
                if ans2 == True:
                    print(f'{n} = {i} + {j}')
                    break

6.实验任务6

task6.py

 

def encoder(text):
    text_1 = list(text)
    text_2 = []
    text_3 = ''
    for i in text_1:
        if 'a'<=i<='z':
            if ord(i)+5>122:
                ans = chr(ord(i)+5-26)
                text_2.append(ans)
            else:
                ans = chr(ord(i)+5)
                text_2.append(ans)
        elif 'A'<=i<='Z':
            if ord(i)+5>90:
                ans = chr(ord(i)+5-26)
                text_2.append(ans)
            else:
                ans = chr(ord(i)+5)
                text_2.append(ans)
        else:
            text_2.append(i)
    for j in text_2:
        text_3 += j
    return(text_3)

def decoder(text):
    text_1 = list(text)
    text_2 = []
    text_3 = ''
    for i in text_1:
        if 'a'<=i<='z':
            if ord(i)-5<97:
                ans = chr(ord(i)-5+26)
                text_2.append(ans)
            else:
                ans = chr(ord(i)-5)
                text_2.append(ans)
        elif 'A'<=i<='Z':
            if ord(i)-5<65:
                ans = chr(ord(i)-5+26)
                text_2.append(ans)
            else:
                ans = chr(ord(i)-5)
                text_2.append(ans)
        else:
            text_2.append(i)
    for j in text_2:
        text_3 += j
    return(text_3)

text = input('输入英文文本：')

encoded_text = encoder(text)
print('编码后的文本：',encoded_text)

decoded_text = decoder(encoded_text)
print('对编码后的文本解码：',decoded_text)

7.实验任务7

task7.py

def collatz(n):
    ans = [n]
    while n >1:
        if n % 2==0:
            n = n//2
        elif n % 2!=0:
            n = n*3+1
        ans.append(n)
    return ans

try:
    t = int(input('Enter a positive integer:'))
    if t <= 0:
        raise ValueError
except ValueError:
    print('Error:must be positive integer')
else:
    print(collatz(t))

8.实验任务8

task.py

def func(n):
    if n == 0:
        return 0
    return 2*func(n-1)+1

while True:
    x = input()
    if x == '#':
        print('计算结束')
        break
    n = int(x)
    ans = func(n)
    print(f'n = {n},ans = {ans}')