How can I count a pandas dataframe over duplications

Question

My initial dataframe is:
    Name        Info1        Info2
0  Name1  Name1-Info1  Name1-Info2
1  Name1  Name1-Info1  Name1-Info2
2  Name1  Name1-Info1  Name1-Info2
3  Name2  Name2-Info1  Name2-Info2
4  Name2  Name2-Info1  Name2-Info2

and i would like to return the number of repetitions of each row as such:
    Name        Info1        Info2  Count
0  Name1  Name1-Info1  Name1-Info2      3
1  Name2  Name2-Info1  Name2-Info2      2

How can I count a pandas dataframe over duplications?

Tom Ron · Accepted Answer

df.groupby(['Name', 'Info1', 'Info2']).size().reset_index().rename(columns={0:"count"})

Sam S · Answer

size = df.groupby('Name').size().tolist()
df = df.groupby('Name').tail(1).reset_index()
df['Count'] = size

JPI93 · Answer

Given your example df:
    Name        Info1        Info2
0  Name1  Name1-Info1  Name1-Info2
1  Name1  Name1-Info1  Name1-Info2
2  Name1  Name1-Info1  Name1-Info2
3  Name2  Name1-Info2  Name1-Info2
4  Name2  Name1-Info2  Name1-Info2

The following:
df.pivot_table(index=list(df), aggfunc='size')

Will return what you're after:
Name   Info1        Info2
Name1  Name1-Info1  Name1-Info2    3
Name2  Name1-Info2  Name1-Info2    2

EddyG · Answer

Add column 'count' and do df.groupby
df['count'] = 1      
df.groupby(['Name', 'Info1', 'Info2'])['count'].sum().reset_index()

How can I count a pandas dataframe over duplications

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