I am trying to populate an array with values from other arrays:

var longitude = responseDoc.getElementsByTagName("lonDD");
var latitude = responseDoc.getElementsByTagName("latDD");
var trackDate = responseDoc.getElementsByTagName("trackDate");

these are all good and have 10 values each. I then define an array:

var pointsArray=new Array(10, 10);

then populate the array:

for(i=0; i<longitude.length; i++){

for (j=0; j <3; j++){

pointsArray[i][j]=longitude[i].firstChild.nodeValue;
pointsArray[i][j]=latitude[i].firstChild.nodeValue;
pointsArray[i][j]=trackDate[i].firstChild.nodeValue;

}
}

This bangs me out when it gets to the third set of values:

pointsArray[i] is undefined

These are the values I'm working with

-2.7532501000, 52.5777060000, 2011-03-26 12:18:04