Sorting renditions ratio

renditions-sort.js

<script type="text/javascript">
    var fapiResponse = {{ albums[0].photos[0].images | json_encode | raw }};
    var renditions = [];
    var ratios = {};

    for (key in fapiResponse) {
        renditions.push(key.split('_retina')[0]);
    }

    renditions.map(function(rendition, i) {
        var dimensions = rendition.split('x');
        var ratio = Math.round(parseInt(dimensions[0], 10) / parseInt(dimensions[1], 10) * 1000) / 1000;

        ratios[ratio] = {
            ratio: ratio,
            rendition: rendition
        }
    });

    console.dir(ratios);
</script>