创建一个包含变量名称和值的字典列表。

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英文:

Create Dictionary with name and value of list of variables

问题

我有一个Python中的变量列表,我想要创建一个字典,其中键将是变量的名称,值将是变量的内容。

a, b, c = 1, 2, 3
my_list = [a, b, c]
my_dict = {f'{item=}'.split('=')[0]: item for item in my_list}

如果我运行上面的代码,我会得到以下结果:

{'item': 3}
但我想要得到以下结果

```python
{'a': 1, 'b': 2, 'c': 3}

提前感谢。

英文:

I have a list of variables in python. And I want to create a dictionary whose key will be the name of the variable and the value will be the content.

a,b,c = 1,2,3
list = [a,b,c]
dic = {f'{item=}'.split('=')[0]:item for item in list}

If I run the previous code, I get as result the following:

{'item': 3}

And i would like to get the following:

{'a':1,'b':2,'c':3}

Thanks in advance

答案1

得分: 1

以下是翻译好的部分:

def namestr(obj, namespace):
    return [name for name in namespace if namespace[name] is obj]

a,b,c = 1,2,3
list = [a,b,c]

d = {f'{namestr(i, globals())[0]}': i for i in list}

这段代码的作用是创建一个字典,将变量名和其对应的值关联起来,得到的结果如下:

{'a': 1, 'b': 2, 'c': 3}

这种方法可能并不是一个好主意,特别是在你的示例中。例如,在Python中,整数是相同的“对象” - 如果我这样写:

a = 1
e = 1
a is e

会得到 True,即使我在测试身份而不是相等性。所以,一旦我有另一个具有与你的示例中相同值的变量,is 测试可能会评估为 True,从而导致错误的结果。举个例子:

def namestr(obj, namespace):
    return [name for name in namespace if namespace[name] is obj]

a,b,c = 1,2,3
list = [a,b,c]
__ = 1

d = {f'{namestr(i, globals())[0]}': i for i in list}

结果是:

{'__': 1, 'b': 2, 'c': 3}

这只是一种解释,说明你可以这样做,而不是你应该以这种方式做。但如果你有一个非常简短的笔记本或其他东西,你知道不会有其他变量重叠,你可能可以这样处理。

英文:

One potential way of doing it is like so (see https://stackoverflow.com/a/592891/11530613):

def namestr(obj, namespace):
    return [name for name in namespace if namespace[name] is obj]

a,b,c = 1,2,3
list = [a,b,c]

d = {f'{namestr(i, globals())[0]}': i for i in list}

This gives:

{'a': 1, 'b': 2, 'c': 3}

This is definitely a bad idea though, especially with your toy example. For example, integers in Python are the same "object"—if I say:

a = 1
e = 1
a is e

I get True, even though I'm testing identity and not equality. So the moment I have another variable with the same value from your toy example above, the is test might evaluate to True, and you could get bad results. Case in point:

def namestr(obj, namespace):
    return [name for name in namespace if namespace[name] is obj]

a,b,c = 1,2,3
list = [a,b,c]
__ = 1

d = {f'{namestr(i, globals())[0]}': i for i in list}

yields

{'__': 1, 'b': 2, 'c': 3}

This is simply an explanation of how you could do it, not that you ever should do it this way. But if you had like, a very short notebook or something and you knew no other variables would ever overlap, you might hack it this way.

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  • 本文由 发表于 2023年2月19日 05:52:24
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