The Geodetic Velocities Visualization expects to find a data file in this directory called beacon-data.json which must be provided.

This JSON file should contain an array of objects, each describing a GPS beacon, including its latitude and longitude position over time.

Example:

[
  {
    "name": "000841",
    "start": 985928400,
    "lon": [139.06990407, 139.069904, 139.06990413, ...],
    "lat": [34.949757897, 34.949757882, 34.949757941, ...]
  },{
    "name": "000842",
    "start": 982818000,
    "lon": [...],
    "lat": [...]
  },{
  ...

  {
    "name": "99R004",
    "start": 1364875200,
    "lon": [...],
    "lat": [...]
  },{
    "name": "99R006",
    "start": 1364875200,
    "lon": [...],
    "lat": [...]
  }
]

For each entry in the array, here are the types and meanings of the fields:

• name - string - The name of the beacon (should be unique).
• start - integer - Unix timestamp of the first GPS reading.
• lon - Array of floats - Longitudinal readings at 1 day increments.
• lat - Array of floats - Latitude readings for each day.

The lon and lat arrays must be the same length for each beacon, but they may be different between beacons.

The special value of 0 in the lon/lat arrays is treated as missing data.