Get row by index in a Dask DataFrame

[danilopeixoto]

What is the appropriate method for obtaining a specific row by index in a Dask DataFrame?

Source

import dask.dataframe as dd


class Dataset:
    def __init__(self, path: str):
        self.df = dd.read_csv(path)

    def __len__(self) -> int:
        return len(self.df)

    def __getitem__(self, index: int) -> list:
        return self.df.loc[index].compute().values[0].tolist()


if __name__ == '__main__':
    dataset = Dataset('wine_dataset/large.csv')

    first_index = 0
    last_index = len(dataset) - 1

    print(f'{first_index=}')
    print(f'{last_index=}')

    print(f'{dataset[first_index]=}')
    print(f'{dataset[last_index]=}')

Output

first_index=0
last_index=155435343
dataset[first_index]=[6.4, 0.28, 0.29, 1.6, 0.052, 34.0, 127.0, 0.9929, 3.48, 0.56, 10.5, 7.0]
Traceback (most recent call last):
  File "dataset.py", line 25, in <module>
    print(f'{dataset[last_index]=}')
  File "dataset.py", line 12, in __getitem__
    return self.df.loc[index].compute().values[0].tolist()
IndexError: index 0 is out of bounds for axis 0 with size 0