slice dataframe pandas code example

Example 1: make new dataframe from slice

# You need copy with boolean indexing, new DataFrame constructor is not necessary:

d2 = d1[d1.a > 1].copy()

Example 2: slicing in pandas

# iloc[row slicing, column slicing]
surveys_df.iloc[0:3, 1:4]

Example 3: slicing in pandas

# Select rows 0, 1, 2 (row 3 is not selected)
surveys_df[0:3]

Example 4: get column pandas

column = df["column_name"]

Example 5: pandas df by row index

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

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