Possible explanation

This error happens when the data bases cannot be loaded into the tool and the main cause might be;

  1. Not providing the correct path to the models folder
  2. providing the wrong pattern to match the models in the directory

Possible solution

  • Ensure you provide the correct path to –models_folder argument
  • Ensure the patterns are provided correctly. In the example below only models which start with en_Brain_ will be selected.

    –models_name_pattern “en_(.*).db”
    –models_name_filter “en_Brain_(.*).db”


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For attribution, please cite this work as

Festus (2021). Unexpected error: nothing to repeat at position 0". PredictDB. /post/2021/07/21/info-unexpected-error-nothing-to-repeat-at-position-0/

BibTeX citation

  title = "Unexpected error: nothing to repeat at position 0"",
  author = "Festus",
  year = "2021",
  journal = "PredictDB",
  note = "/post/2021/07/21/info-unexpected-error-nothing-to-repeat-at-position-0/"