grid: {

            hoverable: true,

            clickable: true,

            autoHighlight:true,

            color: "#999"

        },

        //selection: {mode: "x"}

    };

    var overview_options = {

        legend:{show:false},

        bars: {show:true,barWidth: 2,},

        shadowSize: 0,

        xaxis: {mode: "time", timeformat: "%d/%m/%y",},

        yaxis: {ticks: 3, min: 0,tickDecimals:0,},

        grid: {color: "#999",},

        selection: {mode: "x"}

    };

    /**

    *get dummy data needed in few places

    */

    function getDummyData(label){

        return {"label":label,

         "data":[{"time":0,

             "commits":0,

                 "added":0,

                 "changed":0,

                 "removed":0,

            }],

            "schema":["commits"],

            "color":'#ffffff',

        }

    }

    /**

     * generate checkboxes accordindly to data

     * @param keys

     * @returns

     */

    function generateCheckboxes(data) {

        //append checkboxes

        var i = 0;

        choiceContainerTable.innerHTML = '';

        for(var pos in data) {

            data[pos].color = i;

            i++;

            if(data[pos].label != ''){

                choiceContainerTable.innerHTML += '<tr><td>'+

            }

        }

    }

    /**

     * ToolTip show

     */

    function showTooltip(x, y, contents) {

        var div=document.getElementById('tooltip');

        if(!div) {

            div = document.createElement('div');

            div.id="tooltip";

            div.style.position="absolute";

            div.style.border='1px solid #fdd';

            div.style.padding='2px';

            div.style.backgroundColor='#fee';

            document.body.appendChild(div);

        }

        YUD.setStyle(div, 'opacity', 0);

        div.innerHTML = contents;

        div.style.top=(y + 5) + "px";

        div.style.left=(x + 5) + "px";

        var anim = new YAHOO.util.Anim(div, {opacity: {to: 0.8}}, 0.2);

        anim.animate();

    }

    /**

     * This function will detect if selected period has some changesets

       for this user if it does this data is then pushed for displaying

       Additionally it will only display users that are selected by the checkbox

    */

    function getDataAccordingToRanges(ranges) {

        var data = [];

        var new_dataset = {};

        var keys = [];

        var max_commits = 0;

        for(var key in dataset){

            for(var ds in dataset[key].data){

                commit_data = dataset[key].data[ds];

                if (commit_data.time >= ranges.xaxis.from && commit_data.time <= ranges.xaxis.to){

                    if(new_dataset[key] === undefined){

                        new_dataset[key] = {data:[],schema:["commits"],label:key};

                    }

                    new_dataset[key].data.push(commit_data);

                }

            }