Pandas how to delete alternate rows

Question

I have a pandas dataframe with duplicate ids. Below is my dataframe

id  nbr  type  count 
7   21   High     4  
7   21   Low      6    
8   39   High     2    
8   39   Low      3    
9   13   High     5    
9   13   Low      7    

How to delete only the rows having the type Low

Answer 1

You can also just slice your df using iloc:

df.iloc[::2]

This will step every 2 rows

Answer 2

You can try this way :

df = df[df.type != "Low"]

Answer 3

Another possible solution is to use drop_duplicates

df = df.drop_duplicates('nbr')
print(df)

   id  nbr  type  count
0   7   21  High      4
2   8   39  High      2
4   9   13  High      5

You can also do:

df.drop_duplicates('nbr', inplace=True)

That way you don't have to reassign it.