.. _colon_full:

**-:**\ [**i**\|\ **o**]
    Swap 1st and 2nd column on input and/or output [Default is no
    swapping]. Append **i** to select input only or **o** to select
    output only. [Default affects both]. This option is typically used
    to handle (latitude, longitude) files; see also
    **-i**\ *cols*\ [**+l**][**+s**\ *scale*][**+o**\ *offset*][,\ *...*][,\ **t**\ [*word*]].