

   RRaattiioonnaall AApppprrooxxiimmaattiioonnss ttoo iinn FFrraaccttiioonn FFoorrmm

        fractions(x, ...)

   AArrgguummeennttss::

          x: Array to be approximated.

        ...: Optional additional parameters to be passed to
             rat(x, ...)

   VVaalluuee::

        A character array of the same shape as `x' of rational
        approximations in fraction form.  e.g 0.28571429 ->
        "2/7".

   SSeeee AAllssoo::

        `rational', `rat'.

   EExxaammpplleess::

        # somewhat pointless..
            x <- rep(1:7,1:7)/7
        #compare:
            table(x)
        #with:
            table(fractions(x))

