select row by index pandas code example

Example 1: pandas select row by index

#for single row
df.loc[ index , : ]

# for multiple rows
indices = [1, 20, 33, 47, 52 ]
new_df= df.iloc[indices, :]

Example 2: isolate row based on index pandas

dfObj.iloc[: , [0, 2]]

Example 3: pandas df by row index

indices = [133, 22, 19, 203, 14, 1]
df_by_indices = df.iloc[indices, :]

Example 4: retrieve row by index pandas

rowData = dfObj.loc[ 'b' , : ]

Example 5: dataframe select row by index value

In [1]: df = pd.DataFrame(np.random.rand(5,2),index=range(0,10,2),columns=list('AB'))

In [2]: df
Out[2]: 
          A         B
0  1.068932 -0.794307
2 -0.470056  1.192211
4 -0.284561  0.756029
6  1.037563 -0.267820
8 -0.538478 -0.800654

In [5]: df.iloc[[2]]
Out[5]: 
          A         B
4 -0.284561  0.756029

In [6]: df.loc[[2]]
Out[6]: 
          A         B
2 -0.470056  1.192211

Example 6: add an index column in range dataframe

df = df.loc[df.index.repeat(df['a'])]   
df['c'] = df.groupby(level=0).cumcount() + 1
df = df.reset_index(drop=True)
print (df)
   a  b  c
0  1  x  1
1  2  y  1
2  2  y  2
3  3  z  1
4  3  z  2
5  3  z  3