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                <div class="js-report-sparkline" data-range-low-color="orange" data-range-high-color="green">[0.0297,0.0267,0.0312,0.0330,0.0386,0.0347]</div>

<div class="js-report-sparkline" data-range-low-color="red" data-range-high-color="blue" style="width: 250px">[0.3767,0.8800,2.1001,1.1000,1.300,0.8800,2.1476]</div>


                .js-report-sparkline {
  width: 208px;
  height: 70px;
  margin: 50px auto;
  font-family: sans-serif;
  position: relative;
  * {
    box-sizing: border-box;

  g {

  path {
    stroke-width: 3;
    fill: none;

  .point {
    stroke-width: 2;
    transition: all .3s;

  .bar-rect {
    fill: transparent;
    stroke: none;

  .point.hover {
    stroke-width: 4;

  .chart-container {
    position: relative;

  .chart-tooltip {
    position: absolute;
    background: rgba(0, 0, 0, .8);
    color: white;
    left: 0;
    display: none;
    padding: 2px 5px;
    font-size: 12px;
    border-radius: 5px;
    border: 1px solid rgba(255, 255, 255, 1);
    pointer-events: none;

    .title {
      z-index: 3;
      text-transform: uppercase;
      font-size: 13px;

  .bullet {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    display: block;
    position: absolute;
    right: 5px;
    top: 13px;


                // Metric
$('.js-report-sparkline').each(function(sparklineId) {
    var th = $(this)

        // Instead of splitting with "," we are passing the data in JSON format
        // Because splitting may cause getting datas as string
        // And that breaks scale calculators
        // Also this chain clears the HTML content
        data = $.parseJSON(
  "sparkline-data", th.text())

        // Get width and height of the container
        w = th.width(),
        h = th.height(),

        // Setting the margins
        // You may set different margins for X/Y
        xMargin = 30,
        yMargin = 15,

        // Scale functions
        // Setting the range with the margin
        y = d3.scale.linear()
                    .domain([d3.min(data), d3.max(data)])
                    .range([yMargin, h - yMargin]),
        x = d3.scale.linear()
                    .domain([0, data.length - 1])
                    .range([xMargin, w - xMargin]),

        // Scale functions for creating the gradient fill/stroke
        // Calculating the color according to data in the range of colors
        // That user has passed with the data-range-[high-low]-color attributes
        gradientY = d3.scale.linear()
                            .domain([d3.min(data), d3.max(data)])

        // This is a different margin than the one for the chart
        // Setting the gradient stops from 0% to 100% will cause wrong color ranges
        // Because data points are positioned in the center of containing rect
        percentageMargin = 100 / data.length,
        percentageX = d3.scale.linear()
                              .domain([0, data.length - 1])
                              .range([percentageMargin, 100 - percentageMargin]),

        // Create S
        container ="div"),

        // Create tooltip
        tooltip = container
            .attr("class", "chart-tooltip"),

        // Create SVG object and set dimensions
        vis = container
            .attr("width", w)
            .attr("height", h)

        // Create the group object and set styles for gradient definition
        // Which is about to add in a few lines
        g = vis.append("svg:g")
                .attr("stroke", "url(#sparkline-gradient-" + sparklineId + ")")
                .attr("fill", "url(#sparkline-gradient-" + sparklineId + ")"),

        // Create the line
        // Using cardinal interpolation because we need
        // The line to pass on every point
        line = d3.svg.line()
            .x(function(d, i) { return x(i); })
            .y(function(d) { return h - y(d); }),

        // Create points
        // We are only creating points for first and last data
          // Because that looks cooler :)
        points = g.selectAll(".point")
            .attr("class", "point")
            .attr("cx", function(d, i) { return x(i) })
            .attr("cy", function(d, i) { return h - y(d) })
            .attr("r", function(d, i) { return (i === (data.length - 1) || i === 0) ? 5 : 0; });

    // Append the line to the group
    g.append("svg:path").attr("d", line(data));

    // Bind calculator functions to tooltip
        calcY: y,
        calcX: x

    // Create the gradient effect
    // This is where the magic happens
    // We get datas and create gradient stops with calculated colors
        .attr("id", "sparkline-gradient-" + sparklineId)
        .attr("x1", "0%").attr("y1", "0%").attr("x2", "100%").attr("y2", "0%")
        .attr("gradientUnits", "userSpaceOnUse")
        .append("svg:stop").attr('offset', function(d, i) {
            return ((percentageX(i))) + "%";
        }).attr("style", function(d) {
            return "stop-color:" + gradientY(d) + ";stop-opacity:1";

    // Creating invisible rectangles for a better hover interaction
    // Because otherwise user would need to hover to the line or point
    // Which is a terrible experience
    // Creating full height invisible bars and binding mouse events
    // To do some special stuff like showing data or adding classes to
    // The point in the targeted area
    var rect = g.selectAll(".bar-rect")
        .attr("class", "bar-rect")
        .attr("x", function(d, i) { return x(i) - (w / data.length / 2) })
        .attr("y", 0)
        .attr("width", w / data.length)
        .attr("height", h)
        .on("mouseenter", function(d, i) {
            // Calculate left position
            var $tooltip = $(this).closest(".js-report-sparkline").find(".chart-tooltip")
                                  .html(formatTooltip(d, i)),
                tooltipLeft = $"calcX")(i) - ($tooltip.width() / 2),
                tooltipTop = h - $"calcY")(d) - 40;

            // Position it again
                        left: tooltipLeft + "px",
                        top: tooltipTop + "px"

            // Add hover class to the targeted point
            $(this).parent().parent().find('.point:eq(' + i + ')').attr('class', 'point hover');
        }).on("mouseleave", function(d, i) {
            var $tooltip = $(this).closest(".js-report-sparkline").find(".chart-tooltip");

            // Hide the tooltip

            // Remove hover class from the targeted point
            $(this).parent().parent().find('.point:eq(' + i + ')').attr('class', 'point');

    // Helper function to calculate the HTML content of the tooltip
    // Tooltip may contain any HTML
    function formatTooltip(d, i) {
        return '<div class="title">' + d + '</div>'