function logStrValueX(de,x,w,g,ub,ua) {
  var z = g.getAttributeNS(null, 'zero'), s = g.getAttributeNS(null, 'scale'),
    p = g.getAttributeNS(null, 'precision'), b = g.getAttributeNS(null, 'base'),
    lgmin, lgmax, lgmul;
    lgmin = Math.log(z)/Math.log(b);
    lgmax = Math.log(s)/Math.log(b);
    lgmul = w / (lgmax - lgmin);
  return ub + (Math.pow(b, lgmin*1 + x / lgmul)).toFixed(p) + ua;
}