Pyarrow.lib.arrowinvalid: file is too small to be a well-formed file

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pyarrow.lib.arrowinvalid: file is too small to be a well-formed file

An “arrowinvalid” error in PyArrow is typically thrown when trying to read an Arrow file that is too small to be considered a valid file. This error is raised to prevent attempting to read a file that does not contain the necessary data to be processed correctly.

To better understand this error, let’s look at an example:

         
import pyarrow as pa

# Read an Arrow file
file_path = "data.arrow"
table = pa.Table.from_pandas(df)

# Write the table to a file
with pa.OSFile(file_path, "wb") as f:
   pa.RecordBatchStreamWriter(f, table.schema).write_table(table)

# Try to read the Arrow file that is too small
try:
   table = pa.ipc.open_file(file_path).read_all()
except pa.lib.ArrowInvalid as e:
   print(str(e))

In the above example, we first create an Arrow file by writing a Pandas DataFrame to it. Then, we explicitly try to read the same file using the `open_file` function in `pa.ipc` module provided by PyArrow. However, if the file is too small, the `ArrowInvalid` exception will be raised.

To avoid this error, you should ensure that the Arrow file you are trying to read is valid and contains the necessary data. This can be done by validating the size and content of the file before attempting to read it.

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