Question

我来自PHP背景，我正在尝试打印每次迭代。我无法理解如何在Python中实现它

>>> a0, a1, a2 = [12, 5, 8]
>>> b0, b1, b2 = [5, 9, 11]
>>> categories = [0, 1, 2]
>>> for i in categories:
        print(a+i)

错误：

Traceback (most recent call last):
  File "<stdin>", line 2, in <module>
NameError: name 'a' is not defined
>>> for i in categories:
...    print('a'+i)
... 
Traceback (most recent call last):
  File "<stdin>", line 2, in <module>
TypeError: cannot concatenate 'str' and 'int' objects
>>> for i in categories:
...     print(a+str(i))
... 
Traceback (most recent call last):
  File "<stdin>", line 2, in <module>
NameError: name 'a' is not defined

我知道这是基本的，但我不知道如何解决它。

修改

>>> print a0
12
>>> print a2
8

a0，a1，a2是可变的。因为我有0,1,2 in，所以我不需要手动写a0，a1，a2，b0，b1，b2。

Answer 1

我认为你不会在python中这样做。更多pythonic将值存储为列表或数组，如：

a = [1, 2, 3]
cat = [0, 1, 2]
for i in cat:
    print(a[i])

Answer 2

>>> a0, a1, a2 = [12, 5, 8]
>>> b0, b1, b2 = [5, 9, 11]
>>> categories = [0, 1, 2]

for i in categories:        
    print(eval('a'+str(i)))

eval会将字符串变为变量，打印变量a0，a1，a2

也是如此

output :
12
5
8

Python：如何打印动态变量

2 个答案: