我正在从excel导入数据，其中一些行可能在列中有注解，并且不是dataframe的一部分。例如，下面：

H1            H2           H3

* highlighted cols are PII

sam          red           5
pam          blue          3
rod          green         11
 * this is the end of the data

将上述文件导入dfpa时，看起来如下所示：

dfPA:
Index     H1            H2           H3
1         *highlighted cols are PII
2         sam          red           5
3         pam          blue          3
4         rod          green         11
5         * this is the end of the data

我想删除第一行和最后一行。这就是我所做的。

# get count of cols in df

input: cntcols = dfPA.shape[1]
output: 3

# get count of cols with nan in df

input: a = dfPA.shape[1] - dfPA.count(axis=1)
output: 
0     2
1     3
2     3
4     3
5     2
(where a is a series)

# convert a from series to df

dfa = a.to_frame()

# delete rows where no. of nan's are greater than 'n'

n = 1
for r, row in dfa.iterrows():
    if (cntcols - dfa.iloc[r][0]) > n:
        i = row.name
        dfPA = dfPA.drop(index=i)

这不管用。有办法做到这一点吗？