Possible explanation

This error raise when the multixcan tool does get gwas files which should be concatenated. The error is common when you are provoding multiple gwas files in a directory. The common mistake that brings the issue rises from;

  1. Providing wring path to the gwas_folder argument or a folder which does not contain gwas files
  2. A mismatch in the gwas file pattern provided in the command line argument
  3. Lack of quotes around the pattern provided

Possible solution

  • Ensure the correct path is provided to –gwas_folder
  • Ensure the pattern you provide to –gwas_file_pattern is correct and in quotes, e.g

    –gwas_file_pattern “(.*).txt” #selects all gwas files
    –gwas_file_pattern “Brain_(.*).gz” #selects only gwas files with Brain prefix


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For attribution, please cite this work as

Festus (2021). Unexpected error: No objects to concatenate. PredictDB. /post/2021/07/21/unexpected-error-no-objects-to-concatenate/

BibTeX citation

  title = "Unexpected error: No objects to concatenate",
  author = "Festus",
  year = "2021",
  journal = "PredictDB",
  note = "/post/2021/07/21/unexpected-error-no-objects-to-concatenate/"