aggregate pandas groupby all-CodePudding

i have a dataframe that looks like the one given below.

item_id length height shape color
a       True
a       True
a              False
a              True
a                     True
b       True
b              True
b                     False
b                           True

i want to do something like

data_df.groupby('item_id').all().reset_index()

to convert the dataframe to

item_id length height shape color
a       True   False  True  False
b       True   True   False True

my problem is with color for item a which should be false as it does not exist but it comes out as true.

CodePudding user response：

Does this work for you?

df.groupby('item_id').aggregate(lambda x : False if x.isnull().all() else x.all())

Output

    length  height  shape   color
item_id             
a   True    False   True    False
b   True    True    False   True

CodePudding user response：

You can work on the inverse, which consider blank cells as True:

(~df.drop('item_id', axis=1).eq(False)).groupby(df['item_id']).all()

Output:

         length  height  shape  color
item_id                              
a          True   False   True   True
b          True    True  False   True

Or if you want to consider blank cells as False, you can convert the data to boolean before groupby:

df.drop('item_id',axis=1).astype(bool).groupby(df['item_id']).all()

Output:

         length  height  shape  color
item_id                              
a         False   False  False  False
b         False   False  False  False