How to get number of groups in a groupby object in pandas?

python pandas dataframe group-by pandas-groupby
wolfsatthedoor picture wolfsatthedoor · Jan 5, 2015 · Viewed 37.5k times · Source

This would be useful so I know how many unique groups I have to perform calculations on. Thank you.

Suppose groupby object is called dfgroup.

Answer

BrenBarn picture BrenBarn · Jan 5, 2015

As documented, you can get the number of groups with len(dfgroup).

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