title: What does this error message mean 'pyarrow.lib.ArrowInvalid: Failed to parse string: ' ' as a scalar of type int64'?
body: <p>I'm trying to use the following hugging face optimum model (see : <a href="https://github.com/huggingface/optimumgraphcore/tree/main/examples/text-classification" rel="nofollow noreferrer">https://github.com/huggingface/optimumgraphcore/tree/main/examples/text-classification</a> ) and train it using my own local dataset. My datasets are in .csv file format, and seem to be loading fine. However when I try to run the model using the following commands:</p>
  <pre><code>export TASK_NAME=mnli
  
  python run_glue.py \
    --model_name_or_path bert-base-uncased \
    --ipu_config_name Graphcore/bert-base-ipu \
    --train_file train.csv \
    --test_file test.csv \
    --validation_file validation.csv \
    --do_train \
    --do_predict \
    --max_seq_length 128 \
    --per_device_train_batch_size 32 \
    --pod_type pod4 \
    --learning_rate 2e-5 \
    --num_train_epochs 3 \
    --output_dir ./output/.../
  </code></pre>
  <p>I get the following error</p>
  <blockquote>
  <p>pyarrow.lib.ArrowInvalid: Failed to parse string: ' ' as a scalar of type int64</p>
  </blockquote>
  <p>I'm pretty new to NLP, and just starting out so I'm not sure what I should be doing differently. My instinct is that my database isn't in the correct format, i.e. I'm trying to run an mnli task, and so I currently have my database columns split into 'premise' (text), 'hypothesis'(text) and 'label' (int), but I don't think that the model recognises the first two columns it as a string.</p>
  <p>Thanks for any suggestions!</p>