// find the current page's position in the "nav" array
var locPath = window.location.pathname;
var slash = locPath.lastIndexOf('/');
var period = locPath.lastIndexOf('.php');
var pgName = locPath.substring(slash+1,period+4);
for(i=0; i < nav.length; i++) {
	if(nav[i] == pgName) {
		setPos(i); // see art_nav.js
		break;
	}
}