假设我有一个使用pandas.dataframe的列,如下所示:
index fruits origin attribute
1 apple USA tasty
2 apple France yummy
3 apple USA juicy
4 apple England juicy
5 apple Japan normal
6 banana Canada nice
7 banana Italy good
.....
我想选择yummy apple from France(2)
并从表中移除不匹配的apples
,如下所示:
index fruits origin attribute
1 apple France yummy
2 banana Canada nice
3 banana Italy good
.....
我认为以下内容应该有效。但事实并非如此:
df.drop(df[(df.fruits == "apple") & (df.origin != "France") | (df.fruits == "apple") & (df.attribute != "yummy")].index)
然后我尝试了以下哪些也行不通:
df = df[~df[(df.fruits == "apple") & (df.origin != "France") & (df.attribute != "yummy")]
任何帮助,小伙子?
答案 0 :(得分:3)
如果通过匹配条件选择:
df[(df.fruits != 'apple') | ((df.fruits == 'apple') & (df.origin == 'France') & (df.attribute == 'yummy'))]
#index fruits origin attribute
#1 2 apple France yummy
#5 6 banana Canada nice
#6 7 banana Italy good
如果按不匹配条件删除:需要删除的内容是fruits
为苹果但origin
不匹配France
或attribute
不包含的行#39; t匹配yummy
:
df[~((df.fruits == 'apple') & ((df.origin != 'France') | (df.attribute != 'yummy')))]
# index fruits origin attribute
#1 2 apple France yummy
#5 6 banana Canada nice
#6 7 banana Italy good
答案 1 :(得分:1)
df.query(
'fruits == "apple" & origin == "France" & attribute == "yummy"'
).append(df.query('fruits != "apple"'))
fruits origin attribute
index
2 apple France yummy
6 banana Canada nice
7 banana Italy good