function f = wood1(x)
  ##
  ## A version of the Wood function which takes a column 4-vector
  ## instead of four distinct arguments. See wood.m for more
  ## information.
  ##
  if (length(x) == 4)
    f = wood(x(1), x(2), x(3), x(4));
  else
    f = NA;
  end
end
