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For more information about Nextflow, please visit Nextflow - A DSL for parallel and scalable computational pipelines

Installing Nextflow

Nextflow is meant to run from your home folder on a Linux machine like the HPC.

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  • Line 1: The module load command is necessary to ensure java is available

  • Line 2: This command downloads and assembles the parts of nextflow - this step might take some time.

  • Line 3: When finished, the nextflow binary will be in the current folder so it should be moved to your “bin” folder” so it can be found later.

  • Line 5: Make a temporary folder for Nextflow to create files when it runs.

  • Line 6: Verify Nextflow is working.

  • Lines 7 and 8: Clean up

Nextflow’s Default Configuration

Once Nextflow is installed, there are some settings that should be applied to take advantage of the HPC environment. Nextflow has a hierarchy of configuration files, where the base configuration that is applied to every workflow you run is here:

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Code Block
[[ -d $HOME/.nextflow ]] || mkdir -p $HOME/.nextflow
cat <<EOF > $HOME/.nextflow/config
singularity {
    cacheDir = '$HOME/.nextflow/NXF_SINGULARITY_CACHEDIR'
    autoMounts = true
}
conda {
    cacheDir = '$HOME/.nextflow/NXF_CONDA_CACHEDIR'
}
process {
  executor = 'pbspro'
  scratch = false
  cleanup = false
}
EOF

Preparing Data

Typically, the pipeline you want to run will want the data prepared in a particular way. You can check the pipeline’s help or website for a guide. Accessing help is typically:

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Some pipelines may need file names, and others may want a CSV file with file names, paths to raw data, and other information.

Running Nextflow

When you run Nextflow, it is a good idea to create a folder for the run - this keeps all the files separate and easy to manage.

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To see the output of Nextflow while running as a job, you can use the Nextflow Tower.

Using the Nextflow Tower

Nextflow Tower allow monitoring of Nextflow runs. To use the NFTower, please visit

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