scales-demo.js

var x = d3.scaleLinear()
    .domain([d3.min(data0, function(d){ return d.gpa; }) / 1.05, 
        d3.max(data0, function(d){ return d.gpa; }) * 1.05])
    .range([0, 800]);

var y = d3.scaleLinear()
    .domain([d3.min(data0, function(d){ return d.height; }) / 1.05,
        d3.max(data0, function(d){ return d.height; }) * 1.05])
    .range([500, 0]);