{
  "id": 183999,
  "title": "Why does ECEF have 4 floating numbers?",
  "url": "/competitions/lyft-motion-prediction-autonomous-vehicles/discussion/183999",
  "author_name": "",
  "post_date": "2020-09-18T22:01:00.899774500Z",
  "votes": 1,
  "comment_count": 1,
  "views": 0,
  "content": "<p>If I read online I expect there to be 3 floating numbers to represent the x,y,z coordinates.  But there are four floating numbers given in the meta.json file.  What is the fourth one? <br>\n<a href=\"https://www.spar3d.com/blogs/from-scratch/vol13no15-earth-centered-earth-fixed/#:~:text=Using%20three%20rectangular%20coordinates%20instead,%2DFixed%20(ECEF)%20coordinates\" target=\"_blank\">https://www.spar3d.com/blogs/from-scratch/vol13no15-earth-centered-earth-fixed/#:~:text=Using%20three%20rectangular%20coordinates%20instead,%2DFixed%20(ECEF)%20coordinates</a>.</p>",
  "messages": [
    {
      "id": "1016363",
      "postDate": "09/18/2020 22:01:00",
      "content": "<p>If I read online I expect there to be 3 floating numbers to represent the x,y,z coordinates.  But there are four floating numbers given in the meta.json file.  What is the fourth one? <br>\n<a href=\"https://www.spar3d.com/blogs/from-scratch/vol13no15-earth-centered-earth-fixed/#:~:text=Using%20three%20rectangular%20coordinates%20instead,%2DFixed%20(ECEF)%20coordinates\" target=\"_blank\">https://www.spar3d.com/blogs/from-scratch/vol13no15-earth-centered-earth-fixed/#:~:text=Using%20three%20rectangular%20coordinates%20instead,%2DFixed%20(ECEF)%20coordinates</a>.</p>",
      "rawMarkdown": "If I read online I expect there to be 3 floating numbers to represent the x,y,z coordinates.  But there are four floating numbers given in the meta.json file.  What is the fourth one? \nhttps://www.spar3d.com/blogs/from-scratch/vol13no15-earth-centered-earth-fixed/#:~:text=Using%20three%20rectangular%20coordinates%20instead,%2DFixed%20(ECEF)%20coordinates.",
      "votes": null
    },
    {
      "id": "1016583",
      "postDate": "09/19/2020 05:22:03",
      "content": "<p>The fourth one is yaw. A yaw rotation is a movement around the yaw axis of a rigid body that changes the direction it is pointing, to the left or right of its direction of motion.</p>",
      "rawMarkdown": "The fourth one is yaw. A yaw rotation is a movement around the yaw axis of a rigid body that changes the direction it is pointing, to the left or right of its direction of motion.",
      "votes": null
    }
  ],
  "comments": [
    {
      "id": 1016583,
      "author_name": "mukesh2630",
      "author_url": "",
      "post_date": "09/19/2020 05:22:03",
      "content": "<p>The fourth one is yaw. A yaw rotation is a movement around the yaw axis of a rigid body that changes the direction it is pointing, to the left or right of its direction of motion.</p>",
      "votes": null,
      "replies": []
    }
  ],
  "raw_markdown_by_id": {
    "1016363": "If I read online I expect there to be 3 floating numbers to represent the x,y,z coordinates.  But there are four floating numbers given in the meta.json file.  What is the fourth one? \nhttps://www.spar3d.com/blogs/from-scratch/vol13no15-earth-centered-earth-fixed/#:~:text=Using%20three%20rectangular%20coordinates%20instead,%2DFixed%20(ECEF)%20coordinates.",
    "1016583": "The fourth one is yaw. A yaw rotation is a movement around the yaw axis of a rigid body that changes the direction it is pointing, to the left or right of its direction of motion."
  },
  "source": "meta"
}