python - 删除 Pandas 数据框中的 NaN/NULL 列？

Question

我在 pandas 中有一个 dataFrame，其中几列都有空值。是否有内置函数可以让我删除这些列？

Answer 1

是的，dropna。见 http://pandas.pydata.org/pandas-docs/stable/missing_data.html和 DataFrame.dropna 文档字符串:

Definition: DataFrame.dropna(self, axis=0, how='any', thresh=None, subset=None)
Docstring:
Return object with labels on given axis omitted where alternately any
or all of the data are missing

Parameters
----------
axis : {0, 1}
how : {'any', 'all'}
    any : if any NA values are present, drop that label
    all : if all values are NA, drop that label
thresh : int, default None
    int value : require that many non-NA values
subset : array-like
    Labels along other axis to consider, e.g. if you are dropping rows
    these would be a list of columns to include

Returns
-------
dropped : DataFrame

要运行的具体命令是:

df=df.dropna(axis=1,how='all')