/index.html

## index.html
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>JS Bin</title>
<style id="jsbin-css">
svg {
  height: 1000px;
  width: 1000px;
}
</style>
</head>
<body>
  <svg>
<path id="arc1" fill="none" stroke="#446688" stroke-width="1" />
  </svg>
<script id="jsbin-javascript">
function polarToCartesian(centerX, centerY, radius, angleInDegrees) {
  var angleInRadians = (angleInDegrees-90) * Math.PI / 180.0;

  return {
    x: centerX + (radius * Math.cos(angleInRadians)),
    y: centerY + (radius * Math.sin(angleInRadians))
  };
}

function describeArc(x, y, radius, startAngle, endAngle){

    var start = polarToCartesian(x, y, radius, endAngle);
    var end = polarToCartesian(x, y, radius, startAngle);

    var largeArcFlag = endAngle - startAngle <= 180 ? "0" : "1";

    var d = [
        "M", start.x, start.y,
        "A", radius, radius, 0, largeArcFlag, 0, end.x, end.y
    ].join(" ");

    return d;
}

window.onload = function() {
  document.getElementById("arc1").setAttribute("d", describeArc(150, 100, 50, -90, +90));
};
</script>


<script id="jsbin-source-css" type="text/css">svg {
  height: 1000px;
  width: 1000px;
}</script>

<script id="jsbin-source-javascript" type="text/javascript">function polarToCartesian(centerX, centerY, radius, angleInDegrees) {
  var angleInRadians = (angleInDegrees-90) * Math.PI / 180.0;

  return {
    x: centerX + (radius * Math.cos(angleInRadians)),
    y: centerY + (radius * Math.sin(angleInRadians))
  };
}

function describeArc(x, y, radius, startAngle, endAngle){

    var start = polarToCartesian(x, y, radius, endAngle);
    var end = polarToCartesian(x, y, radius, startAngle);

    var largeArcFlag = endAngle - startAngle <= 180 ? "0" : "1";

    var d = [
        "M", start.x, start.y,
        "A", radius, radius, 0, largeArcFlag, 0, end.x, end.y
    ].join(" ");

    return d;
}

window.onload = function() {
  document.getElementById("arc1").setAttribute("d", describeArc(150, 100, 50, -90, +90));
};
</script></body>
</html>

## jsbin.regicedate.css
svg {
  height: 1000px;
  width: 1000px;
}

## jsbin.regicedate.js
function polarToCartesian(centerX, centerY, radius, angleInDegrees) {
  var angleInRadians = (angleInDegrees-90) * Math.PI / 180.0;

  return {
    x: centerX + (radius * Math.cos(angleInRadians)),
    y: centerY + (radius * Math.sin(angleInRadians))
  };
}

function describeArc(x, y, radius, startAngle, endAngle){

    var start = polarToCartesian(x, y, radius, endAngle);
    var end = polarToCartesian(x, y, radius, startAngle);

    var largeArcFlag = endAngle - startAngle <= 180 ? "0" : "1";

    var d = [
        "M", start.x, start.y,
        "A", radius, radius, 0, largeArcFlag, 0, end.x, end.y
    ].join(" ");

    return d;
}

window.onload = function() {
  document.getElementById("arc1").setAttribute("d", describeArc(150, 100, 50, -90, +90));
};
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width">
	<title>JS Bin</title>
	<style id="jsbin-css">
	svg {
	height: 1000px;
	width: 1000px;
	}
	</style>
	</head>
	<body>
	<svg>
	<path id="arc1" fill="none" stroke="#446688" stroke-width="1" />
	</svg>
	<script id="jsbin-javascript">
	function polarToCartesian(centerX, centerY, radius, angleInDegrees) {
	var angleInRadians = (angleInDegrees-90) * Math.PI / 180.0;

	return {
	x: centerX + (radius * Math.cos(angleInRadians)),
	y: centerY + (radius * Math.sin(angleInRadians))
	};
	}

	function describeArc(x, y, radius, startAngle, endAngle){

	var start = polarToCartesian(x, y, radius, endAngle);
	var end = polarToCartesian(x, y, radius, startAngle);

	var largeArcFlag = endAngle - startAngle <= 180 ? "0" : "1";

	var d = [
	"M", start.x, start.y,
	"A", radius, radius, 0, largeArcFlag, 0, end.x, end.y
	].join(" ");

	return d;
	}

	window.onload = function() {
	document.getElementById("arc1").setAttribute("d", describeArc(150, 100, 50, -90, +90));
	};
	</script>


	<script id="jsbin-source-css" type="text/css">svg {
	height: 1000px;
	width: 1000px;
	}</script>

	<script id="jsbin-source-javascript" type="text/javascript">function polarToCartesian(centerX, centerY, radius, angleInDegrees) {
	var angleInRadians = (angleInDegrees-90) * Math.PI / 180.0;

	return {
	x: centerX + (radius * Math.cos(angleInRadians)),
	y: centerY + (radius * Math.sin(angleInRadians))
	};
	}

	function describeArc(x, y, radius, startAngle, endAngle){

	var start = polarToCartesian(x, y, radius, endAngle);
	var end = polarToCartesian(x, y, radius, startAngle);

	var largeArcFlag = endAngle - startAngle <= 180 ? "0" : "1";

	var d = [
	"M", start.x, start.y,
	"A", radius, radius, 0, largeArcFlag, 0, end.x, end.y
	].join(" ");

	return d;
	}

	window.onload = function() {
	document.getElementById("arc1").setAttribute("d", describeArc(150, 100, 50, -90, +90));
	};
	</script></body>
	</html>