google maps v3 drawing circle using haversine formula and polyline

I am drawing a circle on a map using the haversine formula and google.maps.Polyline. There is an error in my code that is causing the circle to be drawn with a line through it. What is the error that is causing this and how can I correct it? (I need to draw my circle using a Polyline so that I can use the points of the circle to determine if given locations are inside the circle. Therefore, I am not using google.maps.Circle)

see code below:

var address=document.getElementById("address").value;
var radius=document.getElementById("radius").value;
var latitude=40;
var longitude=0;
geocoder.geocode( { 'address': address}, function(results, status){
if (status==google.maps.GeocoderStatus.OK){
latlng=(results[0].geometry.location);
latitude=latlng.lat();
longitude=latlng.lng();
}   

else{
    alert("Geocode was not successful for the following reason: " + status);
}
});





//Degrees to radians 
  var d2r = Math.PI / 180;

  /开发者_运维技巧/  Radians to degrees
 var r2d = 180 / Math.PI;

 // Earth radius is 3,963 miles
 var cLat = (radius / 3963) * r2d;

 var cLng = cLat / Math.cos(latitude * d2r);


  //Store points in array 
  var points = [];
alert("declare array");

  var bounds= new google.maps.LatLngBounds();

  // Calculate the points
  // Work around 360 points on circle
  for (var i=0; i < 360; i++) {

  var theta = Math.PI * (i/16);

  // Calculate next X point 
  circleY = longitude + (cLng * Math.cos(theta));            
   // Calculate next Y point 
  circleX = latitude + (cLat * Math.sin(theta));
    // Add point to array 
    var aPoint=new google.maps.LatLng(circleX, circleY);
    points.push(aPoint);
    bounds.extend(aPoint);

 }
 points.push(points[0]);//to complete circle

var colors=["#CD0000","#2E6444","#003F87" ];

var Polyline_Path = new google.maps.Polyline({
path: points,
strokeColor: colors[count],
// color of the outline of the polygon
strokeOpacity: 1,
// between 0.0 and 1.0
strokeWeight: 1,
// The stroke width in pixels
fillColor: colors[count],
fillOpacity: 0
});
Polyline_Path.setMap(map);

Your value for theta in the loop needs to go from 0 to 2*PI to create a whole circle. Your value is going from 0 to 22.5*PI. This means you are going round the circle 10.25 times, and end up drawing a line from a quarter way round the circle to the point where you started: this is the line you are talking about.

Try using :

var theta = Math.PI * (i / 180);

Although you may also want to cut down the number of points: 360 segments is a lot for a circle. I have found 32 is usually more than enough.

The answer above is correct, but you say you can't use the circle from the API because you want to do a point in polygon check. You should use the Circle class and do a distance check to know if the point is in the circle. You can use your implementation of distance or use the API (google.maps.geometry.spherical.computeDistanceBetween).