Scatterplot, transition + diagonal line

<!DOCTYPE html>
  <head>
    <meta charset="utf-8">
    <script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.5/d3.min.js"></script>
  
		<title>scatterplot|transition</title>
		
		<style type="text/css">
	
			
			h1{
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
  font-size: 26px;
  font-style: bold;
  
}

body {
				background-color: #F9FFFF;
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
  font-size: 16px;
  font-style: bold;

}

svg {
				background-color: #F9FFFF;
			 
      }

.mycirc {
	   stroke-width: 2;
     stroke: #411dae;
     fill: #3adddb;
			
}

.mycirc:hover {
  stroke: #170a3d;
	fill: #181a8f;
}

.axis path,
			.axis line {
				fill: none;
				stroke: black;
				shape-rendering: crispEdges;
			}
			
			.axis text {
				font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
        font-style: bold;
   	  	font-size: 11px;
			}

</style>

<h1>Stop and Frisk Totals by Race for NYC in 2014 </h1>

</head>
	<body>

<p>Original data available at <a href="https://www.nyc.gov/html/nypd/html/analysis_and_planning/stop_question_and_frisk_report.shtml">NYC.gov</a>.</p>

var w = 700;
			var h = 500;
			var padding = [ 20, 20, 50, 80 ];  //Top, right, bottom, left

// scale x data linearly
      			var xScale = d3.scale.linear()
								.range([ padding[3], w - padding[1]])
            ;

// scale y data ordinally
      var yScale = d3.scale.linear()
								.range([ padding[0], h - padding[2] ]);

// add x-axis 
      var xAxis = d3.svg.axis()
							.scale(xScale)
							.orient("bottom")
            //  .tickFormat(d3.format("d"));  //remove comma
               ;

// add y-axis
      			var yAxis = d3.svg.axis()
							.scale(yScale)
							.orient("left");

var svg = d3.select("body")
						.append("svg")
						.attr("width", w)
						.attr("height", h);

d3.csv("stopfrisksum.txt", function(data) {

// inform domain to widthScale - x data
        xScale.domain([ 0, d3.max(data, function(d) {
					return +d.Brooklyn;
				}) ]).nice();

// inform domain to heightScale - y axis
        yScale.domain([  
                        d3.max(data, function(d) {
					             return +d.Queens;
				               })  
                      ,0
                      ])
           .nice();

var circles = svg.selectAll("circle")
								.data(data)
								.enter()
								.append("circle");

// initial characterization of circles
			circles.attr("class", "mycirc")
				    .attr("cx", function(d){return xScale(d.Brooklyn);})
  			  	.attr("cy", function(d) {return yScale(d.Queens);})	
   				 .attr("r", .1)
      		.append("title")
					.text(function(d) {
						return d.race + " individuals were stopped and frisked " + d.total + " times in NYC in 2014";
					});

// transition entrance of cicles
        circles.sort(function(a, b) {
						return d3.ascending(+a.total, +b.total);
					})
					.transition()
					.delay(function(d, i) {
						return i * 250;
					})
					.duration(2000)
					.attr("r", 5);

// add x-axis        
        				svg.append("g")
					.attr("class", "x axis")
					.attr("transform", "translate(0," + (h - padding[2]) + ")")
					.call(xAxis);

// add y-axis
        svg.append("g")
					.attr("class", "y axis")
					.attr("transform", "translate(" + padding[3] + ",0)")
					.call(yAxis);

// add diagonal line
        svg.append("line")
            .attr("x1", xScale(0))
            .attr("y1", yScale(0))
            .attr("x2", xScale(6000))
            .attr("y2", yScale(6000))
            .attr("stroke-width", 2)
            .attr("stroke", "red")
            .attr("stroke-dasharray", "5,5")  //style of svg-line
            ;
        
        // text label for the x axis
       svg.append("text")      
        .attr("x", (w + padding[3]) /2 )
        .attr("y",  h - (padding[3])/7)
        .attr("style","font-size:16px; font-weight: bold;") // to bold title
        .style("text-anchor", "middle")
        .text("Brooklyn Total");

// Add the text label for the Y axis
    svg.append("text")
        .attr("transform", "rotate(-90)")
        .attr("y", padding[3]/3)
        .attr("x", (-h+padding[0])/2)
        .attr("style","font-size:16px; font-weight: bold;") // to bold title
        .style("text-anchor", "middle")
        .text("Queens Total");

});

</script>

</body>
</html>

https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.5/d3.min.js