.. efun::  mixed * unmkmapping(mapping map)

  Take mapping :arg:`map` and return an array of arrays with the keys and values from the mapping.

  The return array has the form ``({ keys[], data0[], data1[], ... })``, with ``keys[]`` being the array of all keys, ``data0[]`` the array of all values in the first column, ``data1[]`` the array of all values in the second column, etc. In particular, the data for ``key[x]`` is stored in ``data0[x]``, ``data1[x]``, etc.

  :efun:`unmkmapping` is inverse to :efun:`mkmapping`, so ``apply(#'mkmapping, unmkmapping(m)) == m``.

  .. usage::

    ::

      mapping m = ([ 1:10;20, 2:11;21 ]);
      unmkmapping(m)
      // returns ({ ({1, 2}), ({ 10, 11 }), ({ 20, 21 }) })

  :history 3.2.6 introduced:

  .. seealso:: :type:`mapping`, :efun:`mappingp`, :efun:`m_indices`, :efun:`m_values`, :efun:`m_delete`, :efun:`sizeof`, :efun:`widthof`.