flink-python/pyflink/examples/table/pandas/conversion_from_dataframe.py

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import logging
import sys

import pandas as pd
import numpy as np

from pyflink.table import (DataTypes, TableEnvironment, EnvironmentSettings)


def conversion_from_dataframe():
    t_env = TableEnvironment.create(EnvironmentSettings.in_streaming_mode())
    t_env.get_config().set("parallelism.default", "1")

    # define the source with watermark definition
    pdf = pd.DataFrame(np.random.rand(1000, 2))
    table = t_env.from_pandas(
        pdf,
        schema=DataTypes.ROW([DataTypes.FIELD("a", DataTypes.DOUBLE()),
                              DataTypes.FIELD("b", DataTypes.DOUBLE())]))

    print(table.to_pandas())


if __name__ == '__main__':
    logging.basicConfig(stream=sys.stdout, level=logging.INFO, format="%(message)s")

    conversion_from_dataframe()