For Loop 和 Series 的真值不明确

Question

在这里查看了类似查询的答案，但仍然不确定。下面的代码产生：

     for i in range(len(df)):
            if df[0]['SubconPartNumber1'].str.isdigit() == False :
                df['SubconPartNumber1'] = df['SubconPartNumber1'].str.replace(',', '/', regex = True)
                df['SubconPartNumber1'] = df['SubconPartNumber1'].str.replace(r"\(.*\)-", '/', regex = True)
ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().

Answer 1

在 pandas 你可以 avoid loops if possible. Your solution should be replace by boolean mask with ~ for invert instead == False and passed to DataFrame.loc:

m = df['SubconPartNumber1'].str.isdigit()
df.loc[~m, 'SubconPartNumber1'] = df.loc[~m, 'SubconPartNumber1'].str.replace(',', '/', regex = True).str.replace(r"\(.*\)-", '/', regex = True)

但是因为numeric只有数字我认为这里不需要掩码，对于or也应该用|加入正则表达式，regex=True是默认参数，所以应该省略:

df = pd.DataFrame({'SubconPartNumber1':['345','aaa,','(bbb)-ccc']})
print (df)
  SubconPartNumber1
0               345
1              aaa,
2         (bbb)-ccc

df['SubconPartNumber1'] = df['SubconPartNumber1'].str.replace(r",|\(.*\)-", '/')
print (df)
  SubconPartNumber1
0               345
1              aaa/
2              /ccc

Answer 2

替换为：

if df[0]['SubconPartNumber1'].str.isdigit() == False :

有了这个：

if df[0]['SubconPartNumber1'].str.isdigit().empty:

除了 empty 之外还有其他方法，但我认为这会满足您的需求。

For Loop 和 Series 的真值不明确

For Loop and The truth value of a Series is ambiguous

python

series

pandas

valueerror