The distances referred to herein are straight line distances and do not account for the curvature of the earth. The distances calculated in GDL are very accurate for points within 50 to 100 miles of each other. As the north-south distance becomes greater, slight errors in calculations can occur. The examples in Table are for points that are oriented directly north or south of the base point, which would have the largest error for the distance given.
| North-South Distance | Maximum Error |
|---|---|
| 50 miles | 0.25% (0.1 miles) |
| 200 miles | 0.9% (1.8 miles) |
| 400 miles | 1.25% (5 miles) |
| 1,000 miles | 1.9% (19 miles) |