daylight.html

<script src="https://cdn.plot.ly/plotly-latest.min.js"></script>
<style> div.plot {width:1200px;height:400px;} </style>

<center>
	<div id="daylight_hours" class="plot"></div>
	<div id="change_minutes" class="plot"></div>

<script>

	function parse (line) {
		var fields = line.split(/\t/)
		var t = +fields[0]
		var v = +fields[1]
		if (v > 24) {v = null}
		return [t, v]
	}

	function change (d,i,a) {
		if (!(i>14&&d[1]&& a[i-14][1])) return null
		var avg = (d[1] - a[i-14][1]) * 60/14
		if (avg > 5 || avg < -5) return null
		return avg
	}

	function display (text) {
		var lines = text.trim().split(/\n/)
		var data = lines.map(parse)
		function x() {return data.map(function (d) {return new Date(d[0]*1000)})}
		function plot(e,f) { Plotly.plot( e, [{ x:x(), y:data.map(f) }], {title: e.id.replace('_',' ') } )}

		plot(daylight_hours, function (d) {return d[1]})
		plot(change_minutes, change)
	}

	Plotly.d3.text('http://c2.com/~ward/arduino/SensorServer/daylight.cgi', display)

</script>

<footer>
	Measured Daylight Hours and<br>14-Day Average Change<br>
	<a href="http://ward.bay.wiki.org/measured-daylight-hours.html">wiki</a>