# pybedtools.bedtool.BedTool.cat

BedTool.cat(*args, **kwargs)

  Concatenate interval files together.

  Concatenates two BedTool objects (or an object and a file) and does an optional post-merge of the features.

  postmerge=True by default; use postmerge=False if you want to keep features separate.

  force_truncate=False by default; force_truncate=True to truncate all files to chrom, start, stop.

  When force_truncate=False and postmerge=False, the output will contain the smallest number of fields observed across all inputs. This maintains compatibility with BEDTools programs, which assume constant number of fields in all lines of a file.

  Other kwargs are sent to `BedTool.merge()` (and assuming that postmerge=True).

  Example usage:

      >>> a = pybedtools.example_bedtool('a.bed')
      >>> b = pybedtools.example_bedtool('b.bed')
      >>> print(a.cat(b))
      chr1    1       500
      chr1    800     950

      >>> print(a.cat(*[b,b],
      ...   postmerge=False))
      chr1    1       100     feature1        0       +
      chr1    100     200     feature2        0       +
      chr1    150     500     feature3        0       -
      chr1    900     950     feature4        0       +
      chr1    155     200     feature5        0       -
      chr1    800     901     feature6        0       +
      chr1    155     200     feature5        0       -
      chr1    800     901     feature6        0       +