Contains error codes for entries in the matrix if there is no route between i and j.
Optional, no need to be added if all routes exist.
| Value | Reason |
|---|
| 0 | No error, a route is available |
| 1 | No route between the origin and destination exists |
| 2 | No valid starting or ending point for the route between the origin and destination locations |
| 3 | The route between the origin and destination exists but includes violations that could make it potentially unusable |
| 4 | The origin and destination locations are either just inside the acceptable range or completely outside the allowed area. Because of this, there are no valid route start or end points for origin and destination locations |
| 99 | Unknown error (for debugging and handling unexpected situations) |
