Test Case Boilerplate
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HTML
<script src="http://code.jquery.com/ui/jquery-ui-git.js"></script>
<link rel="stylesheet" href="http://code.jquery.com/ui/jquery-ui-git.css">
<p>Restricted to y-axis, but drag position is not</p>
<div style="background:red;width:100px;height:100px;"></div>
<pre style="position:absolute;left:150px;top:30px;"></pre>
JavaScript
$('div').draggable({
axis: 'y',
drag: function (e, p) {
$('pre').html('x: ' + p.position.left + '\ny: ' + p.position.top);
}
});