python 整数浮点字符串列表之间的关系

整数的字符串--->整数:

1 a = '123'
2 b = int(a)

浮点的字符串--->整数:

1 a = '123.123'
2 b = int(a)
报错:
Traceback (most recent call last): File
"K:/python/wokespace/apitest/11.py", line 115, in <module> b = int(a) ValueError: invalid literal for int() with base 10: '123.123'

正确写法

1 a = '123.123'
2 b = int(float(a))  #只保留整数部分
# b = round(float(a)) 四舍五入;round为内置函数可直接引用

整数/浮点的字符串--->列表

a = '123'
b = list(a)

整数/浮点---->列表

1 a = 123.123
2 # a = 123
3 b = list(a)
Traceback (most recent call last):
  File "K:/python/wokespace/apitest/11.py", line 115, in <module>
    b = list(a)
TypeError: 'float' object is not iterable

正确写法:

1 #先将整数、浮点类型转为字符串

 

个人样例,仅供参考欢迎指正:

 1 #不使用内置函数,讲浮点型进行四舍五入
 2 N = input('请输入一个浮点数进行四舍五入:')
 3 Num = int(float(N))
 4 D = '.'
 5 if (D not in N):
 6     print('请输入浮点')
 7 elif len(N)>33:
 8     print('请输入32位浮点')
 9 else:
10     n = list(N)
11     # print('n',n)
12     ind = 0
13     for i in range(0,len(n)):
14         if n[i] == '.':
15             ind = i
16             # print('ind:',ind)
17     if int(n[ind+1]) >=5 :
18         Num = Num + 1
19         print('输入的浮点数四舍五入后为',Num)
20     else:
21         print('输入的浮点数四舍五入后为', Num)

 

posted @ 2022-01-19 22:05  鱼骨头~  阅读(70)  评论(0)    收藏  举报