window.onload = choosePic;

var myPix = new Array("img/mago1.jpg","img/mago2.jpg","img/mago3.jpg","img/mago4.jpg","img/mago5.jpg","img/mago5.jpg","img/mago6.jpg","img/mago7.jpg");

function choosePic() {
	randomNum = Math.floor((Math.random() * myPix.length));
	document.getElementById("myPicture").src = myPix[randomNum];
}