```bash
docker run --rm quay.io/biocontainers/bedtools:2.31.1--h13024bc_3 bedtools unionbedg -h
```

Tool:    bedtools unionbedg (aka unionBedGraphs)
Version: v2.31.1
Summary: Combines multiple BedGraph files into a single file,
	 allowing coverage comparisons between them.

Usage:   bedtools unionbedg [OPTIONS] -i FILE1 FILE2 .. FILEn
	 Assumes that each BedGraph file is sorted by chrom/start 
	 and that the intervals in each are non-overlapping.

Options: 
	-header		Print a header line.
			(chrom/start/end + names of each file).

	-names		A list of names (one/file) to describe each file in -i.
			These names will be printed in the header line.

	-g		Use genome file to calculate empty regions.
			- STRING.

	-empty		Report empty regions (i.e., start/end intervals w/o
			values in all files).
			- Requires the '-g FILE' parameter.

	-filler TEXT	Use TEXT when representing intervals having no value.
			- Default is '0', but you can use 'N/A' or any text.

	-examples	Show detailed usage examples.

