A slightly adopted version using SVG. A form to control radius of randomly drawn circles.
<!DOCTYPE html> <html> <head> <title>Hello, data!</title> <script type="text/javascript" src="lib/d3.js"></script> </head> <body> <form name="myform" onSubmit="return handleClick()"> <input name="Submit" type="submit" value="Radius" /> <input type="text" id="myRadius"/> </form> <div id="viz"></div> <script type="text/javascript"> var mySVG = d3.select("#viz") .append("svg:svg") .attr("width", 600) .attr("height", 400); function handleClick(event){ console.log(document.getElementById("myRadius").value) draw(document.getElementById("myRadius").value) return false; } function draw(rad){ mySVG.append("svg:circle") .style("stroke", "black") .style("fill", "grey") .attr("r", rad) .attr("cx", Math.round(Math.random()*600)) .attr("cy", Math.round(Math.random()*400)) } </script> </body> </html>