code: function(init) {
    var i, r = new Float64Array(16);
    if (init) for (i = 0; i < init.length; i++) r[i] = init[i];
    return r;
  }
docs: Ported in 2014 by Dmitry Chestnykh and Devi Mandiri. Public domain.  Implementation derived from TweetNaCl version 20140427. See for details: http://tweetnacl.cr.yp.to/