You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: vector3d.m
    path of file: ./repos/mtex/geometry/@vector3d
    
    the code of the file until where you have to start completion: classdef vector3d < dynOption
%
% The class vector3d describes three dimensional vectors, given by
% their coordinates x, y, z and allows to calculate with them as
% comfortable as with real n
    
function v = X(varargin)
      % the vector (1,0,0)
      %
      % Syntax
      %   x = vector3d.X % returns a single vector (1,0,0)
      %   x = vector3d.X(3,1) % returns 3 vectors (1,0,0)
      
      s = varargin(cellfun(@isnumeric,varargin));
      x = ones(s{:});
      v = vector3d(x,0,0,varargin{:});
    end