njvack · December 21, 2016 21:38
diff --git a/index.html b/index.html
 <!DOCTYPE html>
 <html>
 <head>
 <meta charset="UTF-8" />
 <script type="text/javascript">

 window.console = window.console || {}
 window.console.log = window.console.log || function() {};

 console.log("Hello");

 // Standard sum function
 function sum(ar) {
  return ar.reduce(function(s, val) {
    return s + val;
  }, 0)
 }

 // Numerical mean
 function mean(ar) {
  return sum(ar) / ar.length;
 }

 function avg_square_diffs(ar) {
  var m = mean(ar);
  var sqdiffs = ar.map(function(e) {
    var d = e - m;
    return d * d;
  });
  return mean(sqdiffs);
 }

 // Yup, it's standard deviation
 function stdev(ar) {
  return Math.sqrt(avg_square_diffs(ar));
 }

 var blink_controller = function(cycle_ms, blink_ms, blink_element, record_blinks) {
  var my = {};
  my.cycle_ms = cycle_ms;
  my.blink_ms = blink_ms;
  my.blink_element = blink_element;
  my.record_blinks = record_blinks;
  my.blinks_recorded = 0;
  my.event_list = [];

  my.keep_blinking = false;
  my.started = false;
  my.finished = false;

  function blink_on() {
    my.blink_element.classList.add("on");
    if (my.started) {
      my.blinks_recorded += 1;
      console.log(my.blinks_recorded);
    }
  }

  function blink_off() {
    my.blink_element.classList.remove("on");
    if (my.blinks_recorded >= my.record_blinks) {
      my.finished = true;
      my.stop_blinking();
      var evt = new Event('finish');
      my.blink_element.dispatchEvent(evt);
    }
  }

  function record_blink(timestamp) {
    my.event_list.push({
      "type": "blink_on",
      "timestamp": timestamp,
    });
  }

  var handle_frame = function(timestamp) {
    // console.log("in handle_frame...")
    if (my.keep_blinking) {
      my.last_frame_time = my.last_frame_time || timestamp;
      var elapsed = timestamp - my.last_frame_time;
      // console.log([elapsed, my.blink_remaining, my.cycle_remaining].join("\t"));
      if (isFinite(my.blink_remaining)) {
        my.blink_remaining -= elapsed;
      }
      if (my.blink_remaining <= 0) {
        blink_off();
        my.blink_remaining = NaN;
        //my.event_list.push(["blink_off", timestamp])
        console.log("blink_off\t"+timestamp);
      }

      my.cycle_remaining -= elapsed;
      if (my.cycle_remaining <= 0 ) {
        blink_on();
        my.blink_remaining = my.blink_ms;
        my.cycle_remaining = my.cycle_ms;
        my.event_list.push(
          {
            "type": "blink_on",
            "timestamp": timestamp
        });
        console.log("blink_on\t"+timestamp);
      }
      my.last_frame_time = timestamp;

      if (my.keep_blinking) {
        window.requestAnimationFrame(handle_frame);
      }
    }
  }

  my.start_blinking = function() {
    my.keep_blinking = true;
    my.cycle_remaining = my.cycle_ms;
    my.blink_remaining = my.blink_ms;
    window.requestAnimationFrame(handle_frame);
  }

  my.stop_blinking = function() {
    my.keep_blinking = false;
  }

  function make_sort_function(evt) {
    return function(ke1, ke2) {
      var dist1 = Math.abs(evt.timestamp - ke1.timestamp);
      var dist2 = Math.abs(evt.timestamp - ke2.timestamp);
      return dist1 - dist2;
    };
  }

  function get_blink_events() {
    return my.event_list.filter(function(e) { return e.type == 'blink_on'; });
  }

  function get_press_events() {
    return my.event_list.filter(function(e) { return e.type == 'keypress'; });
  }

  my.match_blinks_and_presses = function() {
    var blinks = get_blink_events();
    var bs = blinks.slice();
    var presses = get_press_events();

    console.log(presses);
    presses.forEach(function(p) {
      console.log("Finding closest blink...");
      console.log(p);
      var sort_fx = make_sort_function(p);
      bs.sort(sort_fx);
      console.log(p);
      var b = bs[0];
      console.log("Closest match:");
      console.log([p.timestamp, b.timestamp]);
      b.press_candidate = b.press_candidate || p;
      var old_diff = Math.abs(b.timestamp, b.press_candidate.timestamp);
      var new_diff = Math.abs(b.timestamp, p.timestamp);
      if (new_diff < old_diff) {
        b.press_candidate = p;
      }
    });
    console.log(blinks);

    return blinks.filter(function(b) { return b.press_candidate; }).map(function(b) {
      return {
        "blink": b,
        "press": b.press_candidate,
        "diff": b.press_candidate.timestamp - b.timestamp
      }
    });
  }

  function record_press(timestamp) {
    my.event_list.push({
      "type": "keypress",
      "timestamp": timestamp
    });
  }

  my.handle_press = function(event) {
    console.log(event);
    if (my.finished) {
      return;
    }
    if (!my.started) {
      console.log("starting to record");
      my.started = true;
    }
    record_press(window.performance.now());
  }

  return my;
 }



 window.addEventListener('load', function() {
  console.log("Loaded");
  var blink_elt = document.getElementById('blinker');
  var record_blinks = 14;
  var blinks_per_minute = 60;
  var cycle_ms = (60 * 1000) / blinks_per_minute;
  var blink_ms = (6/60) * 1000;
  window.bc = blink_controller(cycle_ms, blink_ms, blink_elt, record_blinks);
  document.addEventListener('keydown', bc.handle_press);
  blink_elt.addEventListener('finish', function(e) {
    var res = bc.match_blinks_and_presses();
    var diffs = res.map(function(thing) { return thing.diff; });
    document.getElementById("results").innerHTML = diffs.join("\n");
    var m = mean(diffs);
    var s = stdev(diffs);
    document.getElementById("mean").innerHTML = "Mean: " + m;
    document.getElementById("std").innerHTML = "Stdev: " + s;
  });
  bc.start_blinking();
 });

 </script>

 <style type="text/css">
 #blinker {
  width: 200px;
  height: 200px;
  border-radius: 100px;
  margin: 32px;
 }

 #blinker.on {
  background-color: red;
 }
 </style>
 </head>
 <body>
 <div id="blinker" class="on"> </div>
 <p>Press space when it blinks!</p>
 <pre><div id="results"></div></pre>
 <h3 id="mean"></h3>
 <h3 id="std"></h3>
 </body>
 </html>
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="UTF-8" />
	<script type="text/javascript">

	window.console = window.console \|\| {}
	window.console.log = window.console.log \|\| function() {};

	console.log("Hello");

	// Standard sum function
	function sum(ar) {
	return ar.reduce(function(s, val) {
	return s + val;
	}, 0)
	}

	// Numerical mean
	function mean(ar) {
	return sum(ar) / ar.length;
	}

	function avg_square_diffs(ar) {
	var m = mean(ar);
	var sqdiffs = ar.map(function(e) {
	var d = e - m;
	return d * d;
	});
	return mean(sqdiffs);
	}

	// Yup, it's standard deviation
	function stdev(ar) {
	return Math.sqrt(avg_square_diffs(ar));
	}

	var blink_controller = function(cycle_ms, blink_ms, blink_element, record_blinks) {
	var my = {};
	my.cycle_ms = cycle_ms;
	my.blink_ms = blink_ms;
	my.blink_element = blink_element;
	my.record_blinks = record_blinks;
	my.blinks_recorded = 0;
	my.event_list = [];

	my.keep_blinking = false;
	my.started = false;
	my.finished = false;

	function blink_on() {
	my.blink_element.classList.add("on");
	if (my.started) {
	my.blinks_recorded += 1;
	console.log(my.blinks_recorded);
	}
	}

	function blink_off() {
	my.blink_element.classList.remove("on");
	if (my.blinks_recorded >= my.record_blinks) {
	my.finished = true;
	my.stop_blinking();
	var evt = new Event('finish');
	my.blink_element.dispatchEvent(evt);
	}
	}

	function record_blink(timestamp) {
	my.event_list.push({
	"type": "blink_on",
	"timestamp": timestamp,
	});
	}

	var handle_frame = function(timestamp) {
	// console.log("in handle_frame...")
	if (my.keep_blinking) {
	my.last_frame_time = my.last_frame_time \|\| timestamp;
	var elapsed = timestamp - my.last_frame_time;
	// console.log([elapsed, my.blink_remaining, my.cycle_remaining].join("\t"));
	if (isFinite(my.blink_remaining)) {
	my.blink_remaining -= elapsed;
	}
	if (my.blink_remaining <= 0) {
	blink_off();
	my.blink_remaining = NaN;
	//my.event_list.push(["blink_off", timestamp])
	console.log("blink_off\t"+timestamp);
	}

	my.cycle_remaining -= elapsed;
	if (my.cycle_remaining <= 0 ) {
	blink_on();
	my.blink_remaining = my.blink_ms;
	my.cycle_remaining = my.cycle_ms;
	my.event_list.push(
	{
	"type": "blink_on",
	"timestamp": timestamp
	});
	console.log("blink_on\t"+timestamp);
	}
	my.last_frame_time = timestamp;

	if (my.keep_blinking) {
	window.requestAnimationFrame(handle_frame);
	}
	}
	}

	my.start_blinking = function() {
	my.keep_blinking = true;
	my.cycle_remaining = my.cycle_ms;
	my.blink_remaining = my.blink_ms;
	window.requestAnimationFrame(handle_frame);
	}

	my.stop_blinking = function() {
	my.keep_blinking = false;
	}

	function make_sort_function(evt) {
	return function(ke1, ke2) {
	var dist1 = Math.abs(evt.timestamp - ke1.timestamp);
	var dist2 = Math.abs(evt.timestamp - ke2.timestamp);
	return dist1 - dist2;
	};
	}

	function get_blink_events() {
	return my.event_list.filter(function(e) { return e.type == 'blink_on'; });
	}

	function get_press_events() {
	return my.event_list.filter(function(e) { return e.type == 'keypress'; });
	}

	my.match_blinks_and_presses = function() {
	var blinks = get_blink_events();
	var bs = blinks.slice();
	var presses = get_press_events();

	console.log(presses);
	presses.forEach(function(p) {
	console.log("Finding closest blink...");
	console.log(p);
	var sort_fx = make_sort_function(p);
	bs.sort(sort_fx);
	console.log(p);
	var b = bs[0];
	console.log("Closest match:");
	console.log([p.timestamp, b.timestamp]);
	b.press_candidate = b.press_candidate \|\| p;
	var old_diff = Math.abs(b.timestamp, b.press_candidate.timestamp);
	var new_diff = Math.abs(b.timestamp, p.timestamp);
	if (new_diff < old_diff) {
	b.press_candidate = p;
	}
	});
	console.log(blinks);

	return blinks.filter(function(b) { return b.press_candidate; }).map(function(b) {
	return {
	"blink": b,
	"press": b.press_candidate,
	"diff": b.press_candidate.timestamp - b.timestamp
	}
	});
	}

	function record_press(timestamp) {
	my.event_list.push({
	"type": "keypress",
	"timestamp": timestamp
	});
	}

	my.handle_press = function(event) {
	console.log(event);
	if (my.finished) {
	return;
	}
	if (!my.started) {
	console.log("starting to record");
	my.started = true;
	}
	record_press(window.performance.now());
	}

	return my;
	}



	window.addEventListener('load', function() {
	console.log("Loaded");
	var blink_elt = document.getElementById('blinker');
	var record_blinks = 14;
	var blinks_per_minute = 60;
	var cycle_ms = (60 * 1000) / blinks_per_minute;
	var blink_ms = (6/60) * 1000;
	window.bc = blink_controller(cycle_ms, blink_ms, blink_elt, record_blinks);
	document.addEventListener('keydown', bc.handle_press);
	blink_elt.addEventListener('finish', function(e) {
	var res = bc.match_blinks_and_presses();
	var diffs = res.map(function(thing) { return thing.diff; });
	document.getElementById("results").innerHTML = diffs.join("\n");
	var m = mean(diffs);
	var s = stdev(diffs);
	document.getElementById("mean").innerHTML = "Mean: " + m;
	document.getElementById("std").innerHTML = "Stdev: " + s;
	});
	bc.start_blinking();
	});

	</script>

	<style type="text/css">
	#blinker {
	width: 200px;
	height: 200px;
	border-radius: 100px;
	margin: 32px;
	}

	#blinker.on {
	background-color: red;
	}
	</style>
	</head>
	<body>
	<div id="blinker" class="on"> </div>
	<p>Press space when it blinks!</p>
	<pre><div id="results"></div></pre>
	<h3 id="mean"></h3>
	<h3 id="std"></h3>
	</body>
	</html>