midsize_file Function Does Not Return Median File

[michaelsykes]

From autobin.py:

def midsize_file(fnames):
    """Select the median-size file from several given filenames.

    If an even number of files is given, selects the file just below the median.
    """
    return sorted(fnames, key=lambda f: os.stat(f).st_size
                 )[len(fnames) // 2 - 1]

• Consider 8 files. The median should be the 4th file in this case (median is between 4/5), or list index 3. This is correctly calculated

8 // 2 = 4
4 - 1 = 3

• Consider 7 files. The median should be the 4th file, or list index 3. This is incorrectly calculated as index 2, the value just below the median

7 // 2 = 3
3 - 1 = 2

[tskir]

@michaelsykes Thank you very much for noticing this! I've submitted a PR to fix the issue