The following files are in National Geographic's TOPO! GPS
comma delimited
import/export format plus some additional fields added onto the
end.
These additional fields give some statistical data about the
waypoints.
To import them just set the import column heading to "Ignore" for the
additional
fields. TOPO! version 2.6 will set those columns to "Ignore" as a
default.
Important: Make sure the import settings in the
mapping
program are set for UTM coordinates and the WGS 84 datum if it doesn't
get that data from the import file.
After the last TOPO! field, which is "Message", the fields are
as listed
in the following table. Older files have only the first seven
fields
listed. More recent files (data recorded since August 2001) have
the last four fields pertaining to the elevation data if I marked the
location
with a Garmin Venture, which records the elevation value. Since
January
2002 some waypoints are also being marked with a Garmin 76, which also
records the elevation.
Note: These waypoints are also provided on National
Geographic's
MapXchange site in the form of ".tpg" files. You can open ".tpg"
type files easily without going through the import process. I am
providing these files for those who would like some idea of the
statistical
error in the location of the waypoints.
1. |
Waypoint Count |
Number of GPS waypoint marks included in the mean |
2. |
Easting Maximum Positive |
Maximum easting value minus mean easting (Maximum
positive direction
difference from the mean) |
3. |
Easting Maximum Negative |
Mean easting minus minimum easting value (Maximum
negative direction
difference from the mean) |
4. |
Northing Maximum Positive |
Maximum northing value minus mean northing (Largest
value minus the
mean) |
5. |
Northing Maximum Negative |
Mean northing minus minimum northing value (Mean value
minus the smallest) |
6. |
Easting Standard Deviation |
Square root of the result of the mean of the sum of the
squares minus
the mean squared |
7. |
Northing Standard Deviation |
|
8. |
Elevation Count |
Number of GPS elevations included in the mean |
9. |
Lowest Elevation |
Lowest elevation value in the list of marks that were
averaged together. |
10. |
Highest Elevation |
Highest elevation value in the list that were averaged
together. |
11. |
Elevation Standard Deviation |
|
|