Draw a Regular Polygon in an HTML5 canvas

HTML

<input type="file" id="fileinput" />

CSS

canvas {
    background-color: #333
}

JavaScript

function readFile(event) {

    var file = event.target.files[0]; 
    if (file) {
		var reader = new FileReader();
		reader.readAsText(file);

		reader.onload = function(data) { 
    	var gcode = [];
			var contents = data.target.result.split("\n");
      
			for ( var i=0; i<contents.length; i++ ) {
			    if ( contents[i].match(/^(G0|G1)/i) ) 
			  		gcode.push(contents[i]);
			}
			contents = [];
      console.log(contents);
      console.log(gcode);
      
      var regex = /[+-]?\d+(\.\d+)?/g;
			var str = gcode[5];
			var floats = str.match(regex).map(function(v) { return parseFloat(v); });
			console.log(floats);
	         
	    }  
    } else { 
      alert("Failed to load file");
    }
}

document.getElementById('fileinput').addEventListener('change', readFile, false);