mapper.geo.approximate
mapper geoPushes onto the stack a mapper instance which will transform the input Geo Time Series™ by approximating the location to the given resolution.
Approximation is done by clearing lower bits of the location HHCode. At resolution R, the lower 64 - 2R bits are cleared.
| Resolution | Precision |
|---|---|
| 2 | 10,000 km |
| 4 | 2,500 km |
| 6 | 625 km |
| 8 | 156 km |
| 10 | 39 km |
| 12 | 10 km |
| 14 | 2.5 km |
| 16 | 600 m |
| 18 | 150 m |
| 20 | 40 m |
| 22 | 10 m |
| 24 | 2.5 m |
| 26 | 60 cm |
| 28 | 15 cm |
| 30 | 4 cm |
The exact precision is 40,000 km divided by 2**resolution.