How to check member is exist in specific group in SharePoint2010 using javascript

In SharePoint 2010, if you want to check logged in user exists which particular group using javascript as follow:

function IsGroupMember(GroupName)
{
     var isGroupMember = false;
     $().SPServices(
     {
          operation: "GetGroupCollectionFromUser",
          userLoginName: $().SPServices.SPGetCurrentUser(),
          async: false,completefunc: function(xData, Status)
          {
               if($(xData.responseXML).find("Group[Name='" + GroupName + "']").length == 1)                
               {
                    isGroupMember = true;
               }
          }
     });
     return isGroupMember;
}

The above code returns the Group name of the logged in user.

You can use this function as:

if(IsGroupMember("Human Resources"))
{
     //your code comes here
}