pandas表聚合后某列进行去重计数

Sure, I can help with that! To count the number of unique values in a column after aggregating a Pandas DataFrame, you can use the nunique() method. Here's an example:

import pandas as pd

# Create a sample DataFrame
df = pd.DataFrame({
    'group': ['A', 'B', 'A', 'B', 'A', 'B'],
    'value': [1, 2, 3, 1, 2, 1]
})

# Aggregate the DataFrame by group and count the number of unique values of 'value'
counts = df.groupby('group')['value'].nunique()

print(counts)

This will output:

group
A    3
B    2
Name: value, dtype: int64

I hope that helps!