Breaking News: Grepper is joining You.com. Read the official announcement!

expand pandas dataframe into separate rows

Busy Boar answered on August 17, 2020 Popularity 9/10 Helpfulness 2/10

answer expand pandas dataframe into separate rows

related Split data-frame using Rows

expand pandas dataframe into separate rows

Comment

def explode(df, lst_cols, fill_value='', preserve_index=False):
    # make sure `lst_cols` is list-alike
    if (lst_cols is not None
        and len(lst_cols) > 0
        and not isinstance(lst_cols, (list, tuple, np.ndarray, pd.Series))):
        lst_cols = [lst_cols]
    # all columns except `lst_cols`
    idx_cols = df.columns.difference(lst_cols)
    # calculate lengths of lists
    lens = df[lst_cols[0]].str.len()
    # preserve original index values    
    idx = np.repeat(df.index.values, lens)
    # create "exploded" DF
    res = (pd.DataFrame({
                col:np.repeat(df[col].values, lens)
                for col in idx_cols},
                index=idx)
             .assign(**{col:np.concatenate(df.loc[lens>0, col].values)
                            for col in lst_cols}))
    # append those rows that have empty lists
    if (lens == 0).any():
        # at least one list in cells is empty
        res = (res.append(df.loc[lens==0, idx_cols], sort=False)
                  .fillna(fill_value))
    # revert the original index order
    res = res.sort_index()
    # reset index if requested
    if not preserve_index:        
        res = res.reset_index(drop=True)
    return res

Popularity 9/10 Helpfulness 2/10 Language python

Source: stackoverflow.com

Tags: dataframe expand pandas python rows

Link to this answer
Share Copy Link

Contributed on Aug 17 2020

Busy Boar

0 Answers Avg Quality 2/10

Closely Related Answers

Split data-frame using Rows

Comment

# splitting dataframe by row index
df_1 = df.iloc[:1000,:]
df_2 = df.iloc[1000:,:]
print("Shape of new dataframes - {} , {}".format(df_1.shape, df_2.shape))

Popularity 8/10 Helpfulness 5/10 Language python

Source: www.geeksforgeeks.org

Tags: python rows ro

Link to this answer
Share Copy Link

Contributed on Aug 12 2022

Said KSI

0 Answers Avg Quality 2/10

expand pandas dataframe into separate rows

Contents

More Related Answers

expand pandas dataframe into separate rows

Closely Related Answers

Split data-frame using Rows

Grepper

Documentation

Social

Legal

Contact

Oops, You will need to install Grepper and log-in to perform this action.