What is jQuery for Document.createElementNS()?

function emleGraphicToSvg(aGraphicNode) {
  var lu = function luf(aPrefix){
    switch (aPrefix){
      case 'xhtml': return 'http://www.w3.org/1999/xhtml';
      case 'math':  return 'http://www.w3.org/1998/Math/MathML';
      case 'svg':   return 'http://www.w3.org/2000/svg';
      }
    return '';
    };
  var svg = document.evaluate("svg:svg",
    aGraphicNode, lu, XPathResult.FIRST_ORDERED_NODE_TYPE, null).
    singleNodeValue;
  $(svg).children().remove();
  rect = document.createElementNS(lu('svg'), "rect");
  rect.setAttribute("x", "35");
  rect.setAttribute("y", "25");
   rect.setAttribute("width", "200");
  rect.setAttribute("height", "50");
  rect.setAttribute("class", "emleGraphicOutline");
  svg.appendChild(rect);
  }

The code is a simplified fragment from Emle - Electronic Mathematics Laboratory Equipment JavaScript file emle_lab.js.

The Look-Up-Function, luf(), maps a complete reference to a shorten name for the namespace in the XPath string and createElementNS(). The existing svg:svg is located, removed and replaced by a new rectangle.