pandas '标签 [0] 不在 [索引] 中'
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'the label [0] is not in the [index]'
提问by justin
when I issue following code in python where myfun is the name of my function, B is Panda data frame:
当我在 python 中发出以下代码时，其中 myfun 是我的函数名称，B 是 Panda 数据框：
myfun(B,10)
it gives error at this line in the function
它在函数的这一行给出错误
A=(data.loc[ii]>=A1) & (data.loc[ii]<A2)
where B and data are the same and A1 and A2 are numbers. The error is as follow:
其中 B 和数据相同，A1 和 A2 是数字。错误如下：
'the label [0] is not in the [index]'
I read everything in your website it does not apply to my case. as nobody has explained what this error is talking about.
我阅读了您网站上的所有内容，但不适用于我的情况。因为没有人解释过这个错误在说什么。
Can anyone tell where possibly I can have a problem and how I can fix it? What does even mean to say label [0] is not in [index]? what is label[0] in my case.
谁能告诉我哪里可能有问题以及如何解决？甚至说标签 [0] 不在 [索引] 中是什么意思？什么是标签 [0] 在我的情况下。
回答by Scotty1-
From the pandasdocumentation:
从pandas文档：
DataFrame.loc
Access a group of rows and columns by label(s) or a boolean array. .loc[] is primarily label based, but may also be used with a boolean array. Allowed inputs are:
A single label, e.g. 5 or 'a', (note that 5 is interpreted as a label of the index, and never as an integer position along the index).
A list or array of labels, e.g. ['a', 'b', 'c'].
A slice object with labels, e.g. 'a':'f'.
A boolean array of the same length as the axis being sliced, e.g. [True, False, True].
- A callable function with one argument (the calling Series, DataFrame or Panel) and that returns valid output for indexing (one of the above)
数据框.loc
通过标签或布尔数组访问一组行和列。.loc[] 主要基于标签，但也可以与布尔数组一起使用。允许的输入是：
单个标签，例如 5 或“a”（请注意，5 被解释为索引的标签，而不是沿索引的整数位置）。
标签列表或数组，例如 ['a', 'b', 'c']。
带有标签的切片对象，例如 'a':'f'。
与被切片的轴长度相同的布尔数组，例如 [True, False, True]。
- 一个可调用函数，带有一个参数（调用 Series、DataFrame 或 Panel）并返回有效的索引输出（上述之一）
Since I guess that iiis of type integer, you need to use df.ilocinstead:
因为我猜它ii是整数类型，所以你需要使用df.iloc：
A = (data.iloc[ii] >= A1) & (data.iloc[ii] < A2)
回答by MatAff
This error also occurs when your index doesn't start with 0. I reset my index using the code below which fixed the error.
当您的索引不是以 0 开头时，也会发生此错误。我使用下面修复了错误的代码重置了我的索引。
train_df = train_df.reset_index()
This does not directly address the issue described in the question, but wanted to leave this here for reference in case anyone comes across the same error in future.
这并没有直接解决问题中描述的问题，但希望将其留在这里以供参考，以防将来有人遇到相同的错误。
