function renderMultiSeriesLineChart (dataset,dom_element_to_append_to){

	  	var data = dataset;

	  	var margin = {top: 60, right: 200, bottom: 50, left: 100},
	  	margin2 = { top: 430, right: 10, bottom: 20, left: 40 },
	  	width = 1000 - margin.left - margin.right,
	  	height = 500 - margin.top - margin.bottom,
	  	height2 =  75;

	  	var parseDate = d3.time.format("%Y%m%d").parse;
	  	var bisectDate = d3.bisector(function(d) { return d.date; }).left;

	  	var xScale = d3.time.scale()
	  	.range([0, width]),

	  	xScale2 = d3.time.scale()
        .range([0, width]); // Duplicate xScale for brushing ref later

        var yScale = d3.scale.linear()
        .range([height, 0]);

        // 40 Custom DDV colors
        var color = d3.scale.ordinal().range(["#4CAF50","#F44336"]);

        var xAxis = d3.svg.axis()
        .scale(xScale)
        .orient("bottom"),

        xAxis2 = d3.svg.axis() // xAxis for brush slider
        .scale(xScale2)
        .orient("bottom");

        var yAxis = d3.svg.axis()
        .scale(yScale)
        .orient("left");

        var line = d3.svg.line()
        .interpolate("linear")
        .x(function(d) { return xScale(d.date); })
        .y(function(d) { return yScale(d.rating); })
		//.defined(function(d) { return d.rating; });  // Hiding line value defaults of 0 for missing data

        var maxY; // Defined later to update yAxis

        var svg = d3.select(dom_element_to_append_to).append("svg")
        .attr("width", width + margin.left + margin.right)
        .attr("height", height + margin.top + margin.bottom) //height + margin.top + margin.bottom
        .append("g")
        .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

        // Create invisible rect for mouse tracking
        svg.append("rect")
        .attr("width", width)
        .attr("height", height)
        .attr("x", 0)
        .attr("y", 0)
        .attr("id", "mouse-tracker")
        .style("fill", "white");

        //for slider part-----------------------------------------------------------------------------------

        var context = svg.append("g") // Brushing context box container
        .attr("transform", "translate(" + 0 + "," + 410 + ")")
        .attr("class", "context");

        //append clip path for lines plotted, hiding those part out of bounds
        svg.append("defs")
        .append("clipPath")
        .attr("id", "clip")
        .append("rect")
        .attr("width", width)
        .attr("height", height);
        //end slider part-----------------------------------------------------------------------------------

        color.domain(d3.keys(data[0]).filter(function(key) { // Set the domain of the color ordinal scale to be all the csv headers except "date", matching a color to an issue
        	return key !== "date";
        }));

        data.forEach(function(d) { // Make every date in the csv data a javascript date object format
        	d.date = d.date;
        });

        var categories = color.domain().map(function(name) { // Nest the data into an array of objects with new keys
        	return {
              	name: name, // "name": the csv headers except date
              	values: data.map(function(d) { // "values": which has an array of the dates and ratings
              		return {
              			date: d.date,
              			rating: +(d[name]),
              		};
              	}),
              	visible: true
              };
          });

        xScale.domain(d3.extent(data, function(d) { return d.date; })); // extent = highest and lowest points, domain is data, range is bouding box

        yScale.domain([0, 100
        //d3.max(categories, function(c) { return d3.max(c.values, function(v) { return v.rating; }); })
        ]);

        xScale2.domain(xScale.domain()); // Setting a duplicate xdomain for brushing reference later

        //for slider part-----------------------------------------------------------------------------------

        var brush = d3.svg.brush()//for slider bar at the bottom
        .x(xScale2)
        .on("brush", brushed);

        context.append("g") // Create brushing xAxis
        .attr("class", "x axis1")
        .attr("transform", "translate(0," + height2 + ")")
        .call(xAxis2);

        var contextArea = d3.svg.area() // Set attributes for area chart in brushing context graph
        .interpolate("monotone")
        .x(function(d) { return xScale2(d.date); }) // x is scaled to xScale2
        .y0(height2) // Bottom line begins at height2 (area chart not inverted)
        .y1(0); // Top line of area, 0 (area chart not inverted)
        //plot the rect as the bar at the bottom
        context.append("path") // Path is created using svg.area details
        .attr("class", "area")
        .attr("d", contextArea(categories[0].values)) // pass first categories data .values to area path generator
        .attr("transform", "translate(0," + 15+ ")")
        .attr("fill", "#F1F1F2");

        //append the brush for the selection of subsection
        context.append("g")
        .attr("class", "x brush")
        .call(brush)
        .selectAll("rect")
       	.attr("height", height2 ) // Make brush rects same height
       	.attr("transform", "translate(0," + 15+ ")")
       	.attr("fill", "#E6E7E8");
        //end slider part-----------------------------------------------------------------------------------

        // draw line graph
        svg.append("g")
        .attr("class", "x axis")
        .attr("transform", "translate(0," + height + ")")
        .call(xAxis);

        svg.append("g")
        .attr("class", "y axis")
        .call(yAxis)
        .append("text")
        .attr("transform", "rotate(-90)")
        .attr("y", 6)
        .attr("x", -10)
        .attr("dy", ".71em")
        .style("text-anchor", "end")
        .text("Values");

        var issue = svg.selectAll(".issue")
        .data(categories) // Select nested data and append to new svg group elements
        .enter().append("g")
        .attr("class", "issue");

        issue.append("path")
        .attr("class", "line")
        .style("pointer-events", "none") // Stop line interferring with cursor
        .attr("id", function(d) {
                return "line-" + d.name.replace(" ", "").replace("/", ""); // Give line id of line-(insert issue name, with any spaces replaced with no spaces)
            })
        .attr("d", function(d) {
                return d.visible ? line(d.values) : null; // If array key "visible" = true then draw line, if not then don't
            })
        .attr("clip-path", "url(#clip)")//use clip path to make irrelevant part invisible
        .style("stroke", function(d) { return color(d.name); });

       	// draw legend
		// var legendSpace = 450 / categories.length; // 450/number of issues (ex. 40)
		var legendSpace = 25;

		issue.append("rect")
		.attr("width", 10)
		.attr("height", 10)
		.attr("x", width + (margin.right/4) - 15)
        .attr("y", function (d, i) { return (legendSpace)+i*(legendSpace) - 8; })  // spacing
              .attr("fill",function(d) {
                return d.visible ? color(d.name) : "#F1F1F2"; // If array key "visible" = true then color rect, if not then make it grey
            })
              .attr("class", "legend-box")
              .on("click", function(d){ // On click make d.visible
                d.visible = !d.visible; // If array key for this data selection is "visible" = true then make it false, if false then make it true
                  maxY = findMaxY(categories); // Find max Y rating value categories data with "visible"; true
                  yScale.domain([-10,maxY+10]); // Redefine yAxis domain based on highest y value of categories data with "visible"; true
                  svg.select(".y.axis")
                  .transition()
                  .call(yAxis);

                  issue.select("path")
                  .transition()
                  .attr("d", function(d){
                        return d.visible ? line(d.values) : null; // If d.visible is true then draw line for this d selection
                    })

                  issue.select("rect")
                  .transition()
                  .attr("fill", function(d) {
                  	return d.visible ? color(d.name) : "#F1F1F2";
                  });
          }).call(function(d){ // On click make d.visible
                d.visible = !d.visible; // If array key for this data selection is "visible" = true then make it false, if false then make it true
                  maxY = findMaxY(categories); // Find max Y rating value categories data with "visible"; true
                  yScale.domain([-10,maxY+10]); // Redefine yAxis domain based on highest y value of categories data with "visible"; true
                  svg.select(".y.axis")
                  .transition()
                  .call(yAxis);

                  issue.select("path")
                  .transition()
                  .attr("d", function(d){
                        return d.visible ? line(d.values) : null; // If d.visible is true then draw line for this d selection
                    })

                  issue.select("rect")
                  .transition()
                  .attr("fill", function(d) {
                  	return d.visible ? color(d.name) : "#F1F1F2";
                  });
              })

          .on("mouseover", function(d){

          	d3.select(this)
          	.transition()
          	.attr("fill", function(d) { return color(d.name); });

          	d3.select("#line-" + d.name.replace(" ", "").replace("/", ""))
          	.transition()
          	.style("stroke-width", 2.5);
          })

          .on("mouseout", function(d){
          	d3.select(this)
          	.transition()
          	.attr("fill", function(d) {
          		return d.visible ? color(d.name) : "#F1F1F2";});

          	d3.select("#line-" + d.name.replace(" ", "").replace("/", ""))
          	.transition()
          	.style("stroke-width", 1.5);
          })

          issue.append("text")
          .attr("class", "legend-box-text")
          .attr("x", width + (margin.right/4))
              .attr("y", function (d, i) { return (legendSpace)+i*(legendSpace); })  // (return (11.25/2 =) 5.625) + i * (5.625)
              .text(function(d) { return d.name; });

          // Hover line
          var hoverLineGroup = svg.append("g")
          .attr("class", "hover-line");

          var hoverLine = hoverLineGroup // Create line with basic attributes
          .append("line")
          .attr("id", "hover-line")
          .attr("x1", 10).attr("x2", 10)
          .attr("y1", 0).attr("y2", height + 10)
                    .style("pointer-events", "none") // Stop line interferring with cursor
                    .style("opacity", 1); // Set opacity to zero

                    var hoverDate = hoverLineGroup
                    .append('text')
                    .attr("class", "hover-text overlay")
                    .attr("y", height - (height-40)) // hover date text position
                    .attr("x", width - 150) // hover date text position
                    .style("fill", "#E6E7E8");

                    var columnNames = ["Series 1","Series 2"];


          // Add mouseover events for hover line.
          d3.select("#mouse-tracker") // select chart plot background rect #mouse-tracker
          .on("mousemove", mousemove) // on mousemove activate mousemove function defined below
          .on("mouseout", function() {
          	hoverDate
                  .text(null) // on mouseout remove text for hover date

                  d3.select("#hover-line")
                  .style("opacity", 1); // On mouse out making line invisible
              });



          function mousemove() {

              var mouse_x = d3.mouse(this)[0]; // Finding mouse x position on rect
              var graph_x = xScale.invert(mouse_x); //


              var format = d3.time.format('%b %Y'); // Format hover date text to show three letter month and full year

              hoverDate.text(format(graph_x))
              .attr("transform", "translate(" + -margin.left + "," + height + margin.top/3  + ")" )
              .style("font-size", 15); // scale mouse position to xScale date and format it to show month and year

              d3.select("#hover-line") // select hover-line and changing attributes to mouse position
              .attr("x1", mouse_x)
              .attr("x2", mouse_x)
                  .style("opacity", 1); // Making line visible

              // Legend tooltips // http://www.d3noob.org/2014/07/my-favourite-tooltip-method-for-line.html

              var x0 = xScale.invert(d3.mouse(this)[0]), /* d3.mouse(this)[0] returns the x position on the screen of the mouse. xScale.invert function is reversing the process that we use to map the domain (date) to range (position on screen). So it takes the position on the screen and converts it into an equivalent date! */
              i = bisectDate(data, x0, 1), // use our bisectDate function that we declared earlier to find the index of our data array that is close to the mouse cursor
              /*It takes our data array and the date corresponding to the position of or mouse cursor and returns the index number of the data array which has a date that is higher than the cursor position.*/
              d0 = data[i - 1],
              d1 = data[i],

              /*d0 is the combination of date and rating that is in the data array at the index to the left of the cursor and d1 is the combination of date and close that is in the data array at the index to the right of the cursor. In other words we now have two variables that know the value and date above and below the date that corresponds to the position of the cursor.*/
              d = x0 - d0.date > d1.date - x0 ? d1 : d0;

          };

          //for brusher of the slider bar at the bottom
          function brushed() {

            xScale.domain(brush.empty() ? xScale2.domain() : brush.extent()); // If brush is empty then reset the Xscale domain to default, if not then make it the brush extent

            svg.select(".x.axis") // replot xAxis with transition when brush used
            .transition()
            .call(xAxis);

            maxY = findMaxY(categories); // Find max Y rating value categories data with "visible"; true
            yScale.domain([-10,maxY+10]); // Redefine yAxis domain based on highest y value of categories data with "visible"; true

            svg.select(".y.axis") // Redraw yAxis
            .transition()
            .call(yAxis);

            issue.select("path") // Redraw lines based on brush xAxis scale and domain
            .transition()
            .attr("d", function(d){
                  return d.visible ? line(d.values) : null; // If d.visible is true then draw line for this d selection
              });

        };

          function findMaxY(data){  // Define function "findMaxY"
          var maxYValues = data.map(function(d) {
          	if (d.visible){
                return d3.max(d.values, function(value) { // Return max rating value
                	return value.rating; })
            }
        });
          return d3.max(maxYValues);
      }

  };