* Creates an array that is the symmetric difference of the provided arrays. * See http://en.wikipedia.org/wiki/Symmetric_difference.

* Creates an array of grouped elements, the first of which contains the first * elements of the given arrays, the second of which contains th

* Creates an object composed from arrays of `keys` and `values`. Provide * either a single two dimensional array, i.e. `[[key1, value1], [key