python - 如何一次删除多列字符串中的第一个字符？

Question

我有 6 列对象($19.99、$25.99 等)，我想将它们转换为 float (19.99、25.99 等)。我必须做的第一件事是删除所有这些列的第一个字符。我能够做到这一点。

df['Subtotal_'] = df['Subtotal'].str[1:]
df['Shipping Charge_'] = df['Shipping Charge_'].str[1:]
df['Tax Before Promotions_'] = df['Tax Before Promotions_'].str[1:]
df['Total Promotions_'] = df['Total Promotions_'].str[1:]
df['Tax Charged_'] = df['Tax Charged_'].str[1:]
df['Total Charged_'] = df['Total Charged_'].str[1:]

我想知道是否有办法一次完成所有这些。我尝试了这个，但它不起作用，并且收到错误“AttributeError:'DataFrame'对象没有属性'str'”。

df[['Subtotal_', 'Shipping Charge_', 'Tax Before Promotions_',
    'Total Promotions_', 'Tax Charged_', 'Total Charged_']] = df.loc[:, 'Subtotal':'Total Charged'].str[1:]

Answer 1

试试这个:

cols = ('Subtotal_', 'Shipping Charge_', 'Tax Before Promotions_', 'Total Promotions_', 'Tax Charged_', 'Total Charged_')
for col in cols:
    df[col] = df[col].str[1:]