Subject: | Rounding errors in repeated downloading/uploading data |
Because of rounding errors in converting between mercator meters (integer) and decimal degrees, data that is repeatedly downloaded and uploaded to GPS will be inaccurate.
To repeat:
1. Download a trail from GPS as LatLon file
2. Upload that trail back to GPS
3. Download the trail again as LatLon file
4. Compare two downloads.
Inaccuracy occurs in 5th decimal place. It is in part due to GPS::Lowrance::Trail's rounding off.