get_category_names = function(i) {
        i = parseFloat(i);
         var cat_names = [];
         for (var j = -20; j <= 20; ++j) {
            if (isNaN(i) || Math.abs(j) % 4 !== 0) {
                    cat_names.push("")
                }
            else {
                cat_names.push((i+(j/20)).toFixed(2).toString());
            }
         }
         return cat_names;
        };
    calc_bar_values = function(conf) {
        var bar_values = [];
        var c_inv = 20 - conf;
        var f = 1 - (conf * 0.03);
        {#var x = c_inv * 5 / 2;#}
        var x = (30 * Math.log(c_inv + 1)) / 2;
        if (conf === 0) {
            var uni = 100 / 41;
        for (var j = -20; j <= 20; ++j) {
            if (j !== 0) {
            bar_values.push({y: uni, color: 'black'})
            }
            else {
            bar_values.push({y: uni, color: 'gray'})
            }
        }
        } else {
            for (var j = -20; j <= 20; ++j) {
                if (j >= -c_inv && j <= c_inv) {
                    if (j !== 0) {
                        var j_abs = Math.abs(j);
                        var m = x * Math.pow(f, j_abs - 1) * (1 - f) / (1 - Math.pow(f, c_inv));
                        bar_values.push({y: m, color: 'gray'})
                    } else if (j === 0) {
                        var m = 100 - x * 2;
                        bar_values.push({y: m, color: 'black'})
                    }
                } else {
                    bar_values.push({y: 0, color: 'gray'})
                }
            }
        }

         return bar_values;
    };

     updateBars = function() {
         valuation = parseFloat(document.getElementById("answer").value);
         slid_value = parseInt(document.getElementById("confidence").value); // change ("form")[1] if I want to have the slider without the guess on the same page
         myChart.series[0].setData(calc_bar_values(slid_value));
       myChart.xAxis[0].setCategories(get_category_names(valuation));
       //myChart.series[2].setData([slid_value/2]); // ignore
     };